Weight Loss Injections UK 2026 | Prices, Eligibility & Comparison

Prescription weight-management treatments licensed in the UK include two weekly injections, a daily injection and a newly licensed daily tablet. They produce very different average results. At Slinic they cost between £99 and £285 a month depending on the treatment and the dose you reach; elsewhere in the UK prices run to around £330. This page gives you the answer first — which treatments exist, how they compare, what they cost and who qualifies — and then explains everything underneath it in as much detail as you want.

It is written and maintained by a UK superintendent pharmacist with 25 years in practice, dispensed through a GPhC-registered NHS-contracted pharmacy, and reviewed against current MHRA product information and NICE guidance.

Treatments available at Slinic

All three are prescription-only medicines, supplied only after an individual clinical assessment. Completing an assessment does not guarantee approval. Prices are fixed for 2026 with no subscription and no minimum term.

Quick comparison: the four UK treatments

What to take from this: the two weekly injections dominate on effectiveness, the tablet trades a daily routine for no needles, and liraglutide is now a second-line option for most people.

Which weight loss injection is best?

On average, tirzepatide. SURMOUNT-5 compared it directly against semaglutide 2.4 mg over 72 weeks and found approximately 20.2% mean reduction against approximately 13.7%.

But that is the answer to a different question from the one most people are actually asking.

The best treatment for you is the one you can tolerate and keep taking. A medicine with the strongest trial average delivers nothing if side effects lead you to stop at month three. In practice, the medicine matters — but so do consistency, tolerability, sensible dose decisions and ongoing clinical review. A strong trial average does not guarantee the best individual result.

What weight loss injections cost in the UK

Across the UK market, prices vary widely between providers. The spread is wide because providers structure pricing very differently, and the headline figure frequently is not what you end up paying.

What to take from this: the gap between starting and maintenance price is where budgets go wrong. Plan for the right-hand column.

Delivery £4.99. Fixed 2026 prices, no subscription, no minimum term, no discount code that expires after month one. Prices last verified: 31 July 2026

Are they available on the NHS?

Yes, but far more narrowly than the licence allows, and the position differs by medicine.

• Mounjaro — recommended under NICE TA1026, being phased in across England over approximately 12 years, currently prioritising those with the highest BMI and multiple weight-related conditions
• Wegovy injection — available under NICE TA875, but only initiated within a specialist weight management service, funded for a maximum of two years
• Wegovy pill — not NHS-funded. A NICE appraisal is under way; access is not expected in 2026

Waits for specialist weight management services run from weeks to well over a year depending on area. The reason most people go private is availability, not quality — the current criteria simply exclude the majority of people who meet the licensed threshold. Full NHS section below.

Who qualifies?

Qualifying conditions include type 2 diabetes, prediabetes, high blood pressure, raised cholesterol, obstructive sleep apnoea and cardiovascular disease. For people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background, thresholds are commonly reduced by around 2.5 kg/m².

Meeting a threshold does not mean treatment is suitable. A prescriber reviews your full medical history, every medicine you take, pregnancy status and plans, and any history of disordered eating. Treatment is declined where it would not be safe. Full eligibility section below.

Why patients choose Slinic

The medicine is identical wherever you get it. Tirzepatide dispensed by one registered UK pharmacy is pharmacologically the same as tirzepatide dispensed by another, provided it is genuine licensed stock from the authorised supply chain.

What differs — enormously — is everything around it.

Those are the things worth asking any provider about, including us. The comparing providers section sets out the questions.

Everything below explains the above in full — how these medicines work, who they suit, what to expect month by month, how doses are decided, how side effects are managed, what the evidence actually shows, and how to obtain treatment safely.

What are weight loss injections?

Weight loss injections are prescription medicines that reduce how hungry you feel. They do it by imitating hormones your gut already releases after a meal — the signals that tell your brain you have eaten enough.

The main hormone involved is GLP-1, glucagon-like peptide-1. Every medicine in this category acts on the GLP-1 receptor. One of them, tirzepatide, also acts on a second receptor, GIP — glucose-dependent insulinotropic polypeptide — which is why it is described as a dual agonist rather than a GLP-1 agonist.

All of them are licensed as an adjunct to a reduced-calorie diet and increased physical activity. That word is not filler. None of these medicines is licensed as a standalone intervention, and the trial results everyone quotes were achieved alongside structured dietary and lifestyle support, not instead of it.

The practical consequence is straightforward. The medicine makes eating less considerably easier. It does not decide what fills the smaller amount you now eat, and that determines a great deal about how you feel while losing weight, how much muscle you keep, and how much of the result survives afterwards.

Why they are prescription-only

Every one of these medicines is a prescription-only medicine in the UK. That is not an administrative formality — it reflects that they are potent medicines with defined contraindications, warnings and interactions. Some people should not take them at all. Some should take them only with additional monitoring. Some will be better served by a different treatment entirely.

There is no legal route to obtaining any of them in the UK without a prescription issued by a qualified prescriber following a clinical assessment. Any website offering to supply them without one is operating outside UK medicines law, and what arrives will not have come through the authorised supply chain.

The medicine versus the programme

Two things get conflated constantly in this market, and separating them is the most useful thing you can do before choosing a provider.

The medicine is the molecule. Tirzepatide is tirzepatide; semaglutide is semaglutide. A pen dispensed by one registered UK pharmacy is pharmacologically identical to a pen dispensed by another, provided it is genuine licensed stock from the authorised supply chain.

The programme is everything around it: the depth of the clinical assessment, who reviews your case, whether anyone follows up, how side effects are managed, what happens when progress stalls, and what support exists when you want to stop or switch. This varies enormously between providers, and it is where the actual difference in outcomes lies.

When people compare providers on price alone, they are comparing the identical component and ignoring the variable one. That works in both directions — a higher price does not automatically indicate better clinical support either.

Which weight loss injections are available in the UK?

Four medicines are licensed in the UK for weight management. A fifth group — GLP-1 medicines licensed for type 2 diabetes — is frequently confused with them and is covered at the end of this section.

Mounjaro (tirzepatide)

A once-weekly injection, supplied as a multi-dose KwikPen containing four weekly doses. Manufactured by Eli Lilly.

Tirzepatide is the only dual agonist currently licensed in the UK, acting on both GIP and GLP-1 receptors. It produces the greatest average weight reduction of any licensed weight-management medicine here, and it is the only one available on the NHS through a GP-led route rather than exclusively through specialist services.

Doses run from 2.5 mg to 15 mg weekly, escalated in 2.5 mg steps at intervals of at least four weeks. The recognised maintenance doses are 5 mg, 10 mg and 15 mg.

→ Full detail: Mounjaro UK guide

Wegovy injection (semaglutide)

A once-weekly injection, licensed in the UK for weight management since 2023. Manufactured by Novo Nordisk.

Doses run from 0.25 mg to a standard maintenance dose of 2.4 mg weekly, with a higher-dose 7.2 mg option licensed for people already established on 2.4 mg. Semaglutide is also licensed in the UK for reducing the risk of serious cardiovascular events in people who are overweight or obese with established cardiovascular disease — the only weight-management medicine currently carrying that indication.

→ Full detail: Wegovy UK guide

Wegovy pill (oral semaglutide)

A once-daily tablet, approved by the MHRA on 11 June 2026 as the first oral GLP-1 medicine licensed in the UK for weight management. Same active ingredient as the Wegovy injection.

Doses run from 1.5 mg to 25 mg daily. It must be taken in the morning on an empty stomach after at least eight hours’ fasting, swallowed whole with a sip of plain water, with a waiting period before eating, drinking or taking other oral medicines.

→ Full detail: Wegovy pill UK guide

Our Wegovy pill guide covers dosing, the fasting rule and how it compares with the injection.

Liraglutide (Saxenda and generics)

A once-daily injection, and the oldest medicine in this group. Saxenda was the first weight-loss injection licensed in the UK. Generic liraglutide products — including Nevolat — contain the same active ingredient and differ only in branding, price and non-active ingredients.

Doses escalate weekly to a maintenance dose of 3 mg daily.

Liraglutide produces substantially less average weight reduction than the newer medicines — around 8% at 3 mg over 56 weeks, against roughly 15% to 21% for semaglutide and tirzepatide. It also requires a daily injection rather than a weekly one. It remains in use because the generics are considerably cheaper, because some people tolerate it better, and because a shorter-acting daily medicine suits certain clinical situations.

For most people starting treatment today, one of the weekly options or the tablet is the more effective choice.

How the four compare

Why Ozempic, Rybelsus, Victoza and Trulicity are not weight loss treatments in the UK

This is the single most common source of confusion, and it matters because the products are not interchangeable.

Ozempic is not a weight-loss medicine in the UK. It contains semaglutide — the same molecule as Wegovy — but it is licensed for type 2 diabetes, with a different dose range and titration schedule. Prescribing it for weight loss is off-label, and demand for that purpose has contributed to supply shortages affecting people who need it to manage their diabetes.

Rybelsus is not the Wegovy pill. Both are oral semaglutide, but Rybelsus is licensed only for type 2 diabetes and only up to 14 mg. The Wegovy pill is a higher-strength formulation licensed specifically for weight management. Substituting one for the other is not a decision a patient or a prescriber should make.

How do weight loss injections work?

All of these medicines work through the same basic route: they imitate hormones your gut releases after eating, and amplify the signals those hormones produce.

What they are not

These medicines are not stimulants. They do not raise your metabolic rate, do not burn fat directly, and have nothing in common with the appetite suppressants of previous decades.

They are also not fat blockers. Unlike orlistat, they do not prevent absorption of what you eat.

Weight loss happens because energy intake falls. If intake does not fall — because portion sizes stay the same out of habit, or because reduced appetite is offset by calories from drinks that bypass fullness signalling entirely — results will be limited whatever the dose. This is the most common reason treatment appears not to work, and it is fixable.

Why response varies between people

Variation is substantial, and it is the question patients ask most often. Some people notice a dramatic change in appetite within days of the first dose. Others notice little until a higher dose. A minority respond poorly at any dose.

What you eat during the appetite window. The medicine reduces hunger; it does not decide what fills the smaller amount you now eat. Two people eating the same number of calories can have very different outcomes depending on protein, fibre and how much comes from liquids.

Whether you drink your calories. The most common invisible cause of a poor response. These medicines work through food volume and gastric emptying. Sugary drinks, alcohol, syrup coffees and smoothies deliver calories without triggering any of that.

Muscle mass and what happens to it. Someone who resistance trains and eats adequate protein loses proportionally more fat and less lean tissue, and holds a higher energy requirement while doing it.

Sleep. Short or disrupted sleep raises appetite signalling and works directly against what the medicine is trying to do. It is unglamorous and it matters.

Other medicines. Some antidepressants, antipsychotics, steroids, certain diabetes treatments and some beta blockers are associated with weight gain or make loss harder. Worth reviewing before concluding the treatment has failed.

How consistently the medicine is taken. Adherence and weight loss track each other closely. This is the single biggest modifiable factor and the one people are least likely to report accurately.

Which weight loss injection is most effective?

Tirzepatide produces the greatest average weight reduction of the licensed options, with high-dose semaglutide close behind. That is the short answer. The longer answer is more useful, because “most effective on average” and “most effective for you” are different questions.

What to take from this: only one row pair here comes from a head-to-head trial. The rest cannot be ranked against each other.

Our Mounjaro versus Wegovy comparison goes through this in full.

The one direct comparison

SURMOUNT-5 compared tirzepatide against semaglutide 2.4 mg head to head in 751 adults with obesity and without diabetes over 72 weeks. Mean weight reduction was approximately 20.2% with tirzepatide against approximately 13.7% with semaglutide, with a greater reduction in waist circumference as well.

Two honest caveats. It was an open-label trial conducted in the US and Puerto Rico. And it compared tirzepatide against semaglutide 2.4 mg — not against the 7.2 mg dose now licensed in the UK, which narrows the gap considerably.

What the averages do not tell you

An average contains a wide spread. Some participants lost far more than the mean, some far less. A mean figure presented as an expected personal result is misleading.

Trial conditions are not everyday conditions. Participants received structured dietary support, regular contact and monitoring at an intensity most people do not have.

Duration matters. These are figures at 56 to 72 weeks. Results at 12 weeks look very different.

Tolerability decides more than potency does. The most effective medicine is the one you can actually keep taking. A treatment that produces excellent average results but makes you feel unwell enough to stop at month three delivers nothing.

Weight loss injections versus tablets

Not everyone wants an injection, and there are licensed oral options — though they are not equivalent to one another.

The important distinction is mechanism. The Wegovy pill is a GLP-1 medicine in tablet form and works the same way as the injections. Orlistat-based products work entirely differently, by reducing fat absorption, and produce considerably less weight loss. Mysimba acts on brain appetite pathways through a different route again.

Neither injections nor tablets are inherently safer. All medicines can cause side effects and none should be taken without an assessment confirming they are appropriate for you.

Who can have weight loss injections?

Private eligibility follows the terms of the UK licence, then narrows according to each provider’s clinical governance. The criteria are broadly the same across all four medicines.

Weight-related conditions that may qualify at BMI 27 to under 30

• Type 2 diabetes
• Prediabetes
• High blood pressure
• Dyslipidaemia, including raised cholesterol
• Obstructive sleep apnoea
• Cardiovascular disease

Lower thresholds for some ethnic backgrounds

For people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background, a lower BMI threshold is commonly applied — usually reduced by around 2.5 kg/m² — because cardiometabolic risk occurs at lower BMI in these populations. NICE applies this adjustment in its NHS criteria. Whether and how a private provider applies it is a matter of their clinical policy.

What else is assessed

Full medical history, including anything you might assume is irrelevant.

Every medicine you take — prescription, over-the-counter, herbal and supplements, with the times of day you take them. Omitting something here is one of the more dangerous things a patient can do.

Pregnancy status and plans. None of these medicines is recommended in pregnancy, and this needs establishing before treatment rather than after.

Identity and weight verification. A legitimate provider verifies who you are and confirms your weight rather than accepting a self-reported figure unchecked.

Any current GLP-1 treatment. Two GLP-1 medicines must never be taken together.

Eating disorder history, current or past.

Who should not use weight loss injections?

Three categories are often presented as one undifferentiated list. They are not equivalent, and the distinction is useful.

Licensed contraindications

These are absolute. Treatment must not be used if you have known serious hypersensitivity to the active ingredient or to any of the excipients in the product.

Warnings and precautions in the product information

Pregnancy. Not recommended. If you are planning to conceive, treatment should be discontinued in advance — confirm the specific interval with your prescriber, as it differs between medicines and semaglutide’s long half-life makes it longer than people expect.

Breastfeeding. Discuss with your prescriber before starting.

Pancreatitis. Acute pancreatitis has been reported with GLP-1 receptor agonists, and the MHRA has issued strengthened warnings. A history of pancreatitis requires careful assessment, and symptoms during treatment need urgent attention.

Gallbladder disease and gallstones. Rapid weight loss from any cause increases gallstone risk. Symptoms need reporting rather than tolerating.

Severe gastrointestinal disease, including gastroparesis. Because these medicines slow gastric emptying, pre-existing severe GI disease needs individual assessment.

Kidney impairment. Gastrointestinal fluid loss can precipitate acute kidney injury in susceptible people. Dehydration is the mechanism, which is why fluid intake matters more than it sounds like it should.

Liver impairment. Requires individual assessment.

Diabetic retinopathy. Rapid improvement in blood glucose control has been associated with temporary worsening. Relevant if you have diabetes and existing eye disease.

Hypoglycaemia risk. These medicines alone rarely cause low blood sugar, but risk rises substantially alongside insulin or a sulfonylurea. Those doses may need adjusting by whoever manages your diabetes.

Planned surgery or procedures with sedation or anaesthesia. Delayed gastric emptying increases aspiration risk. Tell your surgical and anaesthetic team well in advance — guidance on how far ahead to stop varies, so have the conversation early rather than the night before.

Thyroid C-cell tumour history. Product information for these medicines addresses personal or family history of medullary thyroid carcinoma and Multiple Endocrine Neoplasia syndrome type 2. Raise any relevant family history at assessment.

Provider-specific clinical exclusions

Beyond the licence, providers apply their own criteria reflecting their clinical governance and the limits of a remote service — commonly current or past eating disorders, certain mental health presentations, complex polypharmacy, or situations better managed face to face. These are legitimate clinical decisions but they are policy rather than universal medical fact, which is why one clinic may decline where another accepts, and why a decline is not necessarily a statement that you can never be treated.

Weight loss injections and specific weight-related conditions

Several conditions are both a reason you might qualify at a lower BMI and a reason treatment needs particular care. The overlap catches people out, because a condition that opens the door to treatment can also be the thing that requires most attention once treatment starts.

Obstructive sleep apnoea

A recognised qualifying condition at BMI 27 to under 30. Weight reduction frequently improves symptoms, sometimes substantially.

The practical consequence is one most people are not warned about: if you use CPAP, your pressure requirements can change as you lose weight. A machine set for your starting weight may become uncomfortable or less effective as your airway anatomy changes. Tell the service that manages your CPAP that you have started treatment, and expect your settings to be reviewed rather than left fixed for the duration.

Do not stop using CPAP on your own initiative because symptoms have improved. That decision belongs with the service managing your sleep apnoea, based on a repeat assessment.

High blood pressure

Also a qualifying condition, and one where treatment often produces a welcome secondary benefit. Blood pressure commonly falls with weight reduction.

That sounds straightforwardly good, and it has a practical catch. If you take antihypertensives, you may become over-treated as your weight falls — the dose that was right at your starting weight may be too much at your new one. Dizziness on standing is usually the first sign.

Report it rather than accepting it as an inevitable side effect of the weight-loss medicine. In most cases it means a medication review is due, not that anything has gone wrong.

Polycystic ovary syndrome

PCOS is not itself on the licensed list of qualifying conditions, but insulin resistance, prediabetes and raised BMI commonly accompany it, and those may qualify.

Two things matter here more than they do for most conditions.

First, weight reduction can restore ovulation in people who were not previously ovulating. Fertility may return unexpectedly, and it may return before you have any reason to think it has. None of these medicines is recommended in pregnancy. Contraception planning is genuinely important and should happen before your first dose rather than after.

Second, insulin resistance often improves alongside weight reduction, which can affect other medicines you take for PCOS. Mention everything at assessment.

Prediabetes

A qualifying condition, and one where treatment has a preventive dimension: weight reduction reduces progression to type 2 diabetes. Your prescriber may want a baseline HbA1c, and may want it repeated during treatment.

Raised cholesterol and dyslipidaemia

A qualifying condition. Lipid profiles commonly improve with weight reduction.

If you take a statin, continue it unless your prescriber advises otherwise. Losing weight is not a reason to stop cardiovascular medication on your own initiative, and improvements in your lipid profile are a reason for review rather than unilateral discontinuation.

Fatty liver disease

Common alongside obesity, and weight reduction is the main intervention. Known liver disease requires individual assessment as part of your consultation, and your prescriber may want liver function tests.

Gallstones

Worth flagging separately because it runs the other way from the conditions above.

Rapid weight loss from any cause increases gallstone risk, and gallbladder events are a recognised effect of GLP-1 treatment. A history of gallstones is not automatically a barrier, but it is something your prescriber needs to know about, and new pain in the upper right abdomen during treatment should be reported rather than tolerated.

Type 2 diabetes

What happens at your first consultation

Knowing what to expect makes the assessment easier to complete properly, and completing it properly is what makes treatment safe.

What you will be asked

• Your height and current weight, and how your weight has changed over time
• Previous weight-loss attempts, including any medication
• Your full medical history, including anything you might assume is irrelevant
• Every medicine you take — prescription, over-the-counter, herbal and supplements, with the times of day you take them
• Whether you are pregnant, breastfeeding, or planning a pregnancy
• Any history of eating disorders
• Whether you have any surgery or procedure planned
• Your alcohol intake
• Family history where relevant to the product warnings
• Your morning routine, if you are considering the tablet — the fasting window has to fit your actual life

Transferring from another provider? See how switching works.

What to have ready

• An accurate current weight — weigh yourself rather than estimating
• A list of your medicines with doses and timings
• Photo ID
• If transferring from another provider: your current medicine, dose, how long you have been on it, and evidence such as a dispensing label or order history

Why complete answers matter more than fast ones

The assessment exists to catch the situations where these medicines would be unsafe for you specifically. Leaving something out does not improve your chance of approval in any way that helps you — it raises the chance of being prescribed something that interacts badly with a medicine you take, or that worsens a condition you have.

Prescribers see incomplete assessments regularly, and the usual outcome is a request for more information, which delays things rather than speeding them up.

What happens next

A UK-registered prescriber reviews what you have submitted. The outcome is one of three things: approval, a request for further information or a video consultation, or a decision that treatment is not appropriate.

That last outcome is not a rejection of you. It is the assessment doing its job.

Your first four weeks: what to expect

The opening month is when most people either settle into treatment or decide it is not for them. Knowing what is normal helps you tell the difference between an adjustment period and a genuine problem.

If side effects are severe rather than mild in the first weeks, contact your prescriber. Severe symptoms are not something to endure as an inevitable part of starting treatment.

How to inject and where

This is an overview. The Instructions for Use supplied with your pen are the authoritative source, and you should read them fully before your first injection.

• Follow your dosing schedule. Weekly medicines are given on the same day each week; daily liraglutide at roughly the same time each day. Weekly doses can be given at any time of day, with or without food
• Check the pen before use. The liquid should be clear and colourless to slightly yellow depending on the product. Do not use it if it is cloudy, discoloured, contains particles, has been frozen, or looks damaged
• Use a new needle every time. Reusing needles blunts the tip, increases pain and injection-site reactions, and risks blockage
• Prepare the dose exactly as described in the Instructions for Use — each pen has its own sequence
• Inject into an approved site and hold the pen in place for the full count specified, so the complete dose is delivered
• Remove the needle immediately afterwards and dispose of it in a sharps bin
• Never store the pen with a needle attached — this causes leaking, can block the needle, and allows air into the cartridge
• Never share your pen, even with a new needle

Approved injection sites

These medicines are injected subcutaneously — into the fat layer just under the skin, not into muscle or a vein.

• The abdomen, avoiding the area immediately around the navel
• The front of the thigh
• The upper arm — for some products this site should be used only when someone else is administering the injection, as it is difficult to reach safely yourself. Check your Instructions for Use

Rotate sites with each injection. Using the same spot repeatedly can cause lumps, hardening or changes in the fat layer under the skin, which can affect how the medicine is absorbed.

Avoid injecting into skin that is bruised, tender, red, hardened, scarred or affected by a skin condition.

If you also inject insulin, use a different site for each medicine.

Practical injection problems and what to do

Monitoring, blood tests and clinical reviews

Treatment does not end at the first prescription, and what happens afterwards varies far more between providers than the medicine itself does.

What ongoing review should cover

• How much weight you have lost and over what period
• Whether side effects are settling, persisting or worsening
• Whether the current dose is right, or whether staying longer is better than escalating
• Any new symptoms, particularly abdominal pain
• Any new medicines you have started
• Whether your other conditions or medicines need reviewing as your weight changes — particularly blood pressure and diabetes medicines
• Your eating pattern, protein intake and activity

Do you need blood tests?

Routine blood monitoring is not universally required for weight-management GLP-1 treatment in the way it is for some medicines. Your prescriber may request baseline or interval tests depending on your circumstances — for example if you have diabetes, kidney or liver concerns, or if a symptom needs investigating.

Blood tests are a clinical judgement based on your history, not a fixed schedule.

Be cautious of a provider that offers no clinical review at all, and equally of one that markets extensive testing you have not been given a clinical reason for.

What to report between reviews

Do not wait for your next review to report severe abdominal pain, persistent vomiting, signs of dehydration, reduced urine output, symptoms of an allergic reaction, or sudden visual changes. Those need attention when they happen.

What should you eat while taking weight loss injections?

Appetite reduction creates an opportunity and a risk at the same time. The opportunity is that eating less becomes far easier. The risk is that eating less of everything — including protein and micronutrients — produces poor nutrition, muscle loss and fatigue.

• Prioritise protein. When total intake falls, protein is the thing most worth protecting, because it helps preserve lean muscle during weight loss
• Include fibre from vegetables, fruit, pulses and wholegrains, adjusted to your symptoms — increase gradually for constipation, moderate it if diarrhoea is the problem
• Keep some healthy fats — olive oil, nuts, oily fish — while noting that very fatty meals commonly worsen nausea early in treatment
• Choose wholegrain carbohydrates over refined where you can
• Eat smaller portions more often rather than three large meals
• Drink enough. Reduced appetite frequently reduces fluid intake without you noticing, and dehydration is the mechanism behind several of the more serious problems
• Do not crash diet. Combining very low calorie intake with a GLP-1 raises the risk of nutritional deficiency, muscle loss, fatigue, hair thinning and gallstones. The medicine already reduces intake substantially; severe restriction on top is counterproductive
• Adapt to your own requirements. Existing medical conditions, allergies and dietary patterns all change what eating well looks like for you

Foods that commonly cause problems

No foods are strictly forbidden. But some reliably make side effects worse, particularly in the days after a dose increase:

• Very fatty and fried food — the most common trigger for nausea
• Large portions late in the evening — a frequent cause of reflux, because gastric emptying is already slowed
• Heavily spiced meals, for some people
• Fizzy drinks — worsen bloating and burping
• Alcohol — covered separately below

Exercise while taking weight loss injections

Any movement counts. Walking is genuinely valuable and needs no equipment, no membership and no planning.

Include resistance exercise. This is the single most effective thing you can do to protect muscle while losing weight — bodyweight exercises, resistance bands or weights, a couple of times a week. It matters more than the cardio most people default to.

Build gradually. Large sudden increases in activity while eating considerably less is a route to exhaustion rather than results.

Stay hydrated, particularly if you have had gastrointestinal side effects.

Scale back when unwell. During periods of nausea or low intake, reduce intensity rather than pushing through.

If you have diabetes, be aware of hypoglycaemia risk around exercise, particularly if you take insulin or a sulfonylurea.

Get medical advice before starting vigorous exercise if you have a heart condition, joint problems or another condition affected by exertion.

Can you drink alcohol on weight loss injections?

There is no absolute prohibition, but there are several reasons for caution.

• It can worsen nausea and reflux, particularly in the days after a dose increase
• It contributes calories — often a significant number, and ones that do not trigger fullness at all, which means they bypass the mechanism the medicine works through
• It can affect blood glucose, which matters more if you take insulin or a sulfonylurea
• It contributes to dehydration, compounding the effect of any gastrointestinal side effects
• Heavy drinking carries risks to the pancreas and liver worth considering alongside a medicine that has pancreatitis among its recognised risks

One thing worth knowing in advance: many people report wanting alcohol less while taking GLP-1 medicines. A reduction in alcohol interest is commonly described and is an area of active research. If it happens to you, it is not a side effect to be concerned about.

Many people drink moderately without difficulty. Discuss your own situation with your prescriber.

Fasting, Ramadan and intermittent fasting

Fasting while taking these medicines raises practical and safety questions, and the forms are affected differently.

On weekly injections

• Hydration is the main concern. These medicines can cause gastrointestinal fluid loss, and a long daily fast on top of that increases dehydration risk. Rehydrating properly during non-fasting hours matters more than usual
• Injection timing is flexible. Weekly doses can be given at any time of day, so schedule for whatever suits you. Keep the minimum interval between doses if you change your day
• Appetite reduction can make it hard to eat enough in a short eating window. Prioritising protein and fluid becomes more important, not less
• If you take insulin or a sulfonylurea, get individual advice before fasting. That combination carries a real hypoglycaemia risk needing planning with your diabetes team

On the daily tablet

The tablet needs more thought, because it already requires a fasted state and a waiting period before eating or drinking. During Ramadan that has to be worked around the pre-dawn meal and the evening break, and the right arrangement will not be obvious.

Plan it with your prescriber or pharmacist in advance rather than improvising during the first week. Switching temporarily to a weekly injection is a legitimate option to discuss.

Intermittent fasting generally

The same considerations apply. Combining aggressive time restriction with a medicine that already substantially reduces intake tends to produce poor nutrition and fatigue rather than better results. If you want to combine them, raise it at review.

Why treatment sometimes does not work

Most people respond well. A minority do not, and the reasons are usually identifiable rather than mysterious. In rough order of how often they turn out to be the explanation:

1. Doses not taken consistently. The most common cause and the least often reported accurately. Adherence and weight loss track each other closely
2. The tablet taken incorrectly. With food, with coffee, or too close to other morning medicines. Absorption falls substantially, and the month looks exactly like non-response
3. Liquid calories. Drinks bypass the satiety mechanism the medicine works through, so appetite reduction never translates into reduced intake
4. Portion sizes unchanged out of habit. Serving the same amount and finishing it, because that is what a meal has always looked like
5. Not enough time at an adequate dose. Judging the medicine at week six, on a titration dose, is judging it before it has been given a chance
6. Another medicine working against it. Some antidepressants, antipsychotics, steroids and diabetes treatments make loss harder. Worth reviewing before concluding the treatment failed
7. An untreated condition. Undiagnosed thyroid disease and poorly controlled diabetes both change what is achievable
8. Genuine non-response. A real but small group. Response to one GLP-1 does not predict response to another, so this is a reason to review options rather than to stop looking

Can you get weight loss injections on the NHS?

Yes, but access is considerably narrower than the licence allows, and it differs by medicine. It helps to separate three things people conflate constantly.

The MHRA licence says who a medicine may legally be prescribed to.

The NICE recommendation says who the NHS should fund it for.

Local commissioning and rollout determine who can actually get it right now, where you live.

Our NHS versus private guide compares both routes in detail.

The four UK nations

NICE appraisals apply to England and, through separate arrangements, generally to Wales and Northern Ireland. Scotland has its own process through the Scottish Medicines Consortium. Local implementation, service availability and waiting times differ across all four nations — if you are outside England, check your own nation’s current position rather than assuming the arrangements above apply.

NHS versus private

NHS weight management services provide high-quality multidisciplinary care, and where you qualify and can access one without a prohibitive wait, that route is well worth pursuing. The reason most people go private is availability, not quality — the current criteria simply exclude the majority of people who meet the licensed threshold.

How much do weight loss injections cost in the UK?

At Slinic, prices run from £99 to £285 per month depending on the medicine and dose. Across the UK market, providers charge up to around £330. That range is wide because providers structure pricing very differently, and the headline figure is frequently not what you end up paying.

See our full cost breakdown and UK provider price comparison.

Why the advertised price and the real cost differ

Dose-based pricing. Most providers charge more for higher strengths. Since almost everyone starts at the bottom of the ladder, the advertised price is usually the lowest you will ever pay.

Subscription models. Some providers require a monthly commitment with a minimum term or a cancellation window.

First-order discount codes. Very common. A discount on the first order that reverts from month two changes the annual figure considerably.

Consultation and delivery charges. Included by some providers, added at checkout by others.

Consumables. Needles and a sharps bin are needed for injections and are not always supplied.

The only meaningful comparison is total cost over twelve months at the dose you are likely to be on, with everything included.

Slinic prices

Delivery is £4.99 per order. Prices last verified: 31 July 2026

The figure that matters is not the entry price — it is what you pay once you reach a maintenance dose and stay there. Do that arithmetic before you start rather than discovering it at month four. See our provider price comparison and full cost breakdown.

How much weight can you lose?

The trial evidence is genuinely strong and it is routinely misrepresented. The headline figures appear in the table further up this page. What follows is what those figures actually mean.

No provider can accurately predict how much weight an individual will lose. Published figures describe averages across study populations, not guaranteed personal outcomes.

Dose escalation: how it works and why

Every one of these medicines starts low and increases in steps. The reason is tolerability — starting at a maintenance dose would produce gastrointestinal side effects severe enough that most people would stop.

The stated interval is a minimum, not a schedule. Four weeks is the point at which an increase may be considered. It does not mean every patient should increase every four weeks. Staying longer at a dose is a legitimate clinical decision and often the right one.

Increases should not be automatic. They should follow a review of how you are responding and how well you are tolerating the current dose. Increasing while significant symptoms persist usually worsens those symptoms without improving results.

Steps should not be skipped. Jumping strengths without prescriber authorisation substantially increases the risk of adverse effects.

Our dosing schedule guide sets out each step in full. The maximum dose is not the goal. If appetite is well controlled and weight is coming down steadily at a lower dose, there is no clinical reason to increase simply because a higher strength exists.

Side effects of weight loss injections

Most side effects are gastrointestinal, most appear during titration or shortly after a dose increase, and most settle as the body adjusts.

Our complete side effects guide covers each symptom and how to manage it.

Reducing side effects

• Eat smaller portions. Because gastric emptying is slower, a normal meal can feel like a large one. The single most effective adjustment for most people.
• Eat slowly and stop when full. Fullness signals arrive earlier than you are used to.
• Avoid very fatty and fried food, particularly in the days after a dose increase.
• Keep fluids up. Reduced appetite usually reduces drinking too, and mild dehydration worsens nausea, fatigue and constipation.
• Do not increase your dose while significant symptoms persist.
• Ask a pharmacist before adding any remedy. Delayed gastric emptying affects how oral medicines are absorbed.

Contact NHS 111 or your prescriber promptly for: vomiting or diarrhoea that will not settle; pain in the upper right abdomen, yellowing of the skin or eyes, or pale stools; passing much less urine than usual after a period of vomiting or diarrhoea; sudden changes in vision, particularly if you have diabetes; significant changes in mood, or thoughts of harming yourself; any symptom that worries you.

Long-term safety: what is known and what isn’t

This section exists because most pages on this subject skip it, and it is the question thoughtful patients actually ask.

What the evidence supports

GLP-1 receptor agonists have been in clinical use for type 2 diabetes since 2005, which means the medicine class has a longer real-world safety record than the weight-management licences suggest. Liraglutide and semaglutide have been used at scale for years. The major weight-management trials ran for 56 to 72 weeks, with extension data beyond that for some products.

Semaglutide has cardiovascular outcome data supporting a reduction in serious cardiovascular events in people who are overweight or obese with established cardiovascular disease — which is why it carries that additional UK indication.

What remains uncertain

Very long-term use. Most people in the trials were treated for 12 to 18 months. Data on continuous use over five, ten or twenty years is still accumulating, because the weight-management indications are recent.

Tirzepatide has a shorter record than semaglutide or liraglutide, simply because it is newer.

Long-term effects of repeated stopping and restarting are not well characterised, though this is now a common real-world pattern.

Lean mass outcomes over many years are an active area of research rather than a settled question.

Protecting muscle while losing weight

Weight loss from any cause — medication, surgery, dieting — includes some lean tissue as well as fat. This matters more than most patients are told, and it is one of the few things genuinely within your control.

Why it matters

Muscle is metabolically active tissue. Losing a large proportion of it lowers your energy requirement, which makes maintaining the result harder later. It also affects strength, balance and function, which matters increasingly with age.

What actually helps

Resistance exercise. The single most effective protective measure. Bodyweight work, resistance bands or weights, a couple of times a week. It does not need to be a gym.

Adequate protein. When total intake falls, protein is the thing most worth protecting. Food first — meat, fish, eggs, dairy, beans, lentils, tofu, pulses. Supplements are worth considering only where food intake genuinely cannot meet requirements.

Not crash dieting on top of the medicine. These medicines already reduce intake substantially. Adding severe restriction increases the risk of nutritional deficiency, muscle loss, fatigue, hair thinning and gallstones without improving results.

Establishing it during treatment, not after. People who build resistance training and protein habits while on treatment retain far more of their result when they stop.

Missed doses, storage and travel

Missed doses

Never take two doses to make up for a missed one. Doubling up substantially increases side-effect risk and does not improve results.

Storage

Travel

• Injections travel in hand luggage — hold luggage is not temperature controlled and may freeze
• Use a cool bag with a temperature pack, with the pen not touching the pack directly
• Carry a copy of your prescription or a pharmacy letter for security
• Take a travel sharps container and check disposal rules at your destination
• Plan your dosing day around time zone shifts, keeping the minimum interval between doses
• Take spare needles and a few days’ extra supply
• The tablet needs none of this — no cold chain, no sharps, no cool bag

Switching between treatments and providers

Switching provider

Transferring pharmacy is normal and does not mean starting treatment again from scratch. You may be able to continue at your current dose, depending on your treatment history and how long you have been at that strength.

You will need evidence of your current treatment — a dispensing label, prescription record, letter from your previous provider, or order history showing dose and dates. Without it, a prescriber cannot safely continue you at a higher dose.

A prolonged gap may mean restarting lower. Tolerance can reduce during a break, so returning directly to your previous dose can produce side effects considerably worse than before. This is a safety decision, not an administrative one.

Switching between medicines

Moving between GLP-1 treatments is common and done regularly. But there is no official published dose-equivalence table between these medicines for weight management. Any switch is a clinical judgement based on your current dose, how long you have taken it, how you tolerated it and how you responded.

The one defined exception: the licence allows people established on the 2.4 mg weekly Wegovy injection to transition directly to the 25 mg daily Wegovy pill on their prescriber’s advice. Below that point the numbers are not proportional.

See our switching guide and provider comparisons: vs Boots · vs MedExpress · vs Simple Online Pharmacy · vs VOY · vs Juniper

What happens when you stop?

Appetite generally returns. The effect on appetite signalling stops when the medicine does.

Weight regain is common and well documented. In SURMOUNT-4, participants who switched to placebo after 36 weeks of tirzepatide regained a substantial proportion of what they had lost, while those who continued kept losing. STEP 4 showed the same pattern with semaglutide.

This is not a personal failure. Obesity is a chronic condition, and treatments for chronic conditions generally stop working when they are stopped. The same is true of blood pressure medicine.

Habits built during treatment matter enormously. People who used the treatment period to establish sustainable eating patterns, regular activity and resistance training retain considerably more of their result.

If you have already stopped and want to begin again, see our guide to restarting after a break.

Three broad paths

Continuing at a maintenance dose. For many people with a chronic condition this is the appropriate answer, and the trial evidence supports it.

Reducing to a lower dose. Some people maintain well on less. A prescriber decision, not something to trial independently.

Stopping with a maintenance plan. Possible, and far more likely to work where sustainable habits are already established rather than being started at the point of stopping.

How to buy weight loss injections safely in the UK

The demand for these medicines has created a substantial illegitimate market. The MHRA has seized thousands of falsified or unlicensed weight-loss injections in recent years, including products claiming to contain semaglutide, tirzepatide and retatrutide, and there have been documented cases of people being hospitalised after using products bought outside the regulated supply chain.

Absolute red flags

Social media sellers. Instagram, TikTok, Facebook groups and messaging apps are not legal supply routes for prescription medicines. A seller operating there is, by definition, operating outside UK medicines law.

Any offer to supply without a prescription. If a website will sell you these medicines without a clinical assessment and a prescriber, it is not a legitimate UK pharmacy. This is the single clearest indicator that whatever arrives did not come through the authorised supply chain.

Imported pens. Products sourced outside the UK may not be licensed here, may not be the formulation approved for UK use, and carry no guarantee that cold chain was maintained.

Anyone else’s medication. Sharing prescription medicines is unsafe and illegal. A pen prescribed for another person was dispensed after an assessment of their medical history.

Prices that make no commercial sense. These medicines have a wholesale cost. A price far below the market range is a strong signal the product is not what it claims to be.

How to verify a provider

1. Find the GPhC registration number, then look it up on the General Pharmaceutical Council register yourself. A number displayed on a website proves nothing until you verify it independently.
2. Check who owns and runs it. A legitimate pharmacy names its superintendent pharmacist and provides a real UK address and working phone number.
3. Confirm a genuine clinical assessment takes place. A three-question form is not a clinical assessment.
4. Check who the prescriber is — a UK-registered doctor, pharmacist prescriber or nurse prescriber, registered with the GMC, GPhC or NMC.
5. Ask how cold chain is maintained in transit for injectable treatment.
6. Read the payment terms. Is it a subscription? Can you cancel? Does the price change after month one?
7. Check what ongoing clinical support is included. Who reviews dose increases? Is there anyone to contact when side effects appear?
8. Be wary of guarantees. No legitimate provider can guarantee approval before assessing you.

If you have already used a product bought outside the regulated route, speak to a pharmacist or your GP. If you have symptoms that concern you, contact NHS 111, or 999 in an emergency.

How to start treatment

1. Complete the online clinical assessment. Answer fully and honestly — the assessment only protects you if it is complete.
2. Provide verification: identity, current weight, and evidence of previous treatment if transferring.
3. A UK-registered prescriber reviews your information.
4. Attend a video consultation where the clinical pathway requires one.
5. Receive a prescribing decision — approval, a request for more information, or a decision that treatment is not appropriate.
6. Approved treatment is prepared for dispatch in temperature-controlled packaging where required.
7. Complete a clinical check-in before each repeat supply.

What to have ready

• An accurate current weight — weigh yourself rather than estimating
• A list of your medicines, with doses and the times you take them
• Photo ID
• If transferring: your current medicine, dose, duration and evidence such as a dispensing label

Completing an assessment does not guarantee approval. These are prescription-only medicines, and clinical safety takes priority over speed.

When weight loss injections are not the right answer

A page like this one has an obvious commercial incentive to present treatment as the solution. It is not always.

If your BMI is below the licensed threshold, treatment is not appropriate, and no legitimate provider will supply it.

If your relationship with food or your body is the primary problem, a medicine that suppresses appetite may make things worse rather than better. Current or past eating disorders need addressing with appropriate support first, and a good assessment will screen for this.

If you are looking for a short-term fix before an event, this is the wrong tool. Meaningful change takes months, the medicine costs money throughout, and stopping is commonly followed by regain.

If you cannot sustain the cost, starting and stopping repeatedly is worse than not starting. Plan for the maintenance dose price, not the starting dose price.

If a symptom needs investigating, that comes first. Unexplained weight change, abdominal pain or other symptoms need a diagnosis before a weight-management medicine is layered on top.

What evidence supports weight loss injections?

Every figure quoted on this page comes from a specific trial with a specific population, duration and design. Those details matter, because they determine how far the result generalises to you. Here is what each major trial actually found, and what it does not tell you.

SURMOUNT-1 — tirzepatide

Studied adults with obesity, or overweight with a weight-related complication, without type 2 diabetes, over 72 weeks alongside lifestyle intervention. Mean weight reduction was approximately 15% at 5 mg, approximately 19.5% at 10 mg and approximately 20.9% at 15 mg, against approximately 3.1% on placebo (Jastreboff et al., N Engl J Med 2022;387:205–216).

A note on the two figures you will see quoted. NEJM reports both a treatment-regimen estimand (approximately 20.9% at 15 mg, which includes participants who stopped treatment) and an efficacy estimand (approximately 22.5%, for those who remained on treatment). Both are correct; they answer different questions. This page uses the treatment-regimen figure throughout, because it reflects what happens across everyone who starts treatment rather than only those who complete it.

Limitation: participants received structured support at trial intensity, and the population excluded people with type 2 diabetes — who typically lose somewhat less on the same treatment.

SURMOUNT-4 — what happens when tirzepatide stops

The most important trial for anyone thinking about stopping. Participants took tirzepatide for 36 weeks, then were randomised either to continue or to switch to placebo for a further 52 weeks.

During the randomised withdrawal period, those who continued lost a further 5.5% of body weight measured from week 36. Those switched to placebo regained 14.0% measured from week 36 — not from the original baseline (Aronne et al., JAMA 2024;331:38–48). A later analysis found that among those who had lost at least 10% during the lead-in, most regained a quarter or more of that loss within a year of stopping, with a corresponding reversal of cardiometabolic improvements.

Limitation: a randomised withdrawal design tells you what happens when treatment stops abruptly under trial conditions. It does not tell you what happens with a planned taper alongside established habits, which is the situation most patients are actually in.

SURMOUNT-5 — tirzepatide against semaglutide

Compared the two directly in 751 adults with obesity and without diabetes over 72 weeks. Mean reduction was approximately 20.2% with tirzepatide against approximately 13.7% with semaglutide, with greater waist circumference reduction as well (Aronne et al., N Engl J Med 2025;393:26–36).

Limitation: open-label, conducted in the US and Puerto Rico, and — importantly — it compared tirzepatide against semaglutide 2.4 mg, not against the 7.2 mg dose now licensed in the UK. A difference in group averages also does not predict which medicine will suit any individual.

STEP 1 — semaglutide 2.4 mg

Studied once-weekly semaglutide 2.4 mg in adults with overweight or obesity without type 2 diabetes over 68 weeks alongside lifestyle intervention. Mean reduction was approximately 14.9%, against approximately 2.4% on placebo, and around 86% of participants lost at least 5% of body weight (Wilding et al., N Engl J Med 2021;384:989–1002).

STEP 4 — what happens when semaglutide stops

Participants took semaglutide for 20 weeks, then either continued or switched to placebo. Those who continued kept losing weight. Those who switched regained a substantial proportion of what they had lost. The effect depends on continued exposure — there is no period after stopping during which the benefit persists on its own.

STEP UP — semaglutide 7.2 mg

A phase 3b trial of around 1,400 adults with obesity and without type 2 diabetes over 72 weeks, comparing 7.2 mg against 2.4 mg and placebo. Mean reduction at 7.2 mg was approximately 19–21% depending on the analysis, against approximately 16–18% at 2.4 mg. Around a third of participants on 7.2 mg lost 25% or more of body weight — roughly double the proportion at 2.4 mg.

Worth knowing in advance: dysaesthesia — an altered or tingling skin sensation — was reported by close to a quarter of participants at 7.2 mg, considerably more than at 2.4 mg. In the large majority it resolved while treatment continued. It is not dangerous, but it is unsettling if nobody has mentioned it, and it leads some people to stop treatment unnecessarily.

Limitation: the headline percentage varies between published figures depending on which statistical analysis is quoted, which is why a range is given rather than a single number.

OASIS 4 — oral semaglutide

Studied oral semaglutide 25 mg in 307 adults with overweight or obesity without diabetes over 64 weeks. Mean reduction was approximately 16.6%, against approximately 2.2% on placebo (Wharton et al., N Engl J Med 2025;393:1077–1087). This is the trial that supported the MHRA approval.

Limitation: a smaller trial than the injection studies, and a shorter duration. It has not been compared head to head against the injection at maintenance dose.

SCALE — liraglutide

Liraglutide 3 mg produced average reduction of around 8% over 56 weeks at maintenance dose, against approximately 0.2% on placebo.

Limitation: an older trial programme with a different comparator landscape. The result is substantially lower than the newer medicines, which is the main reason liraglutide is now a second-line choice for most people.

How clinicians decide whether to continue treatment

Continuation is a decision at every review, not a default. A prescriber is weighing several things.

Is it working? Clinical guidance for weight-management medicines generally looks for a meaningful response within a defined period at an adequate dose — NICE uses a 5% threshold at six months for NHS semaglutide. Private prescribing is not bound by that figure, but the principle is sound: treatment that is not producing a response after a fair trial deserves a rethink rather than indefinite continuation.

Is it tolerated? Ongoing significant side effects at a stable dose are a reason to change something — the dose, the form, or the medicine.

Has anything changed medically? New symptoms, new diagnoses, a planned pregnancy, planned surgery, or a new medicine can all change the picture.

Is it still the right tool? Someone who has reached their goal and is maintaining is having a different conversation from someone mid-treatment.

What does the patient want? This belongs on the list. Treatment is a decision made with you, and a prescriber who never asks what you actually want from it is not doing the job properly.

Common mistakes to avoid

• Increasing the dose too quickly. The stated interval is a minimum, not a target
• Doubling up after a missed dose. Never
• Trying to extract an extra dose from a finished pen. The residual liquid is overfill, not a dose, and cannot be measured accurately
• Sharing a pen. Unsafe regardless of needle changes, because of blood-borne infection risk
• Reusing needles. A new one every time
• Buying outside the regulated supply chain. The most dangerous item on this list
• Ignoring severe symptoms. Severe abdominal pain in particular needs urgent attention, not waiting to see
• Letting yourself get dehydrated. Easily done when appetite drops
• Eating too little protein. Costs you muscle, and muscle is hard to get back
• Stopping abruptly with no plan. Weight regain is likely without one
• Not disclosing a medicine or a condition. The assessment only protects you if it is complete
• Using two GLP-1 medicines together. Never, in any combination
• Assuming the maximum dose is the goal. The best dose is the lowest one that works for you
• Comparing your progress to other people’s. Response varies enormously, and the comparison rarely helps

Common myths about weight loss injections

Weight loss injections versus weight loss surgery

A question worth answering directly, because the two are often presented as competing options when they serve overlapping but different situations.

Medication is not a lesser version of surgery, and surgery is not a failure of medication. They suit different clinical situations, and for some people medication is a route to becoming a safer surgical candidate rather than an alternative to it.

If you are considering surgery, that conversation belongs with a bariatric service rather than an online provider. If you are on a surgical waiting list and thinking about starting medication in the meantime, tell both teams.

Weight loss injections versus dieting alone

The honest comparison, because it is the one most people are actually weighing up.

In the clinical trials, placebo groups also received structured dietary and lifestyle support — and they lost weight. Typically around 2% to 3% of body weight over the trial period. The medicine groups lost considerably more. That difference is the effect of the medicine, and it is substantial.

But two things follow that are worth stating plainly.

Dietary change works. It is just extremely hard to sustain. The problem with lifestyle intervention alone has never been that it does not produce weight loss. It is that hunger increases as you lose weight, and most people cannot override that indefinitely. What these medicines do is reduce that hunger, which makes sustained change possible for people who could not sustain it before.

The medicine does not replace the dietary change. Every trial result quoted on this page was achieved alongside a reduced-calorie diet and increased activity. The licence says adjunct for a reason.

If you have never made a structured attempt at dietary change with proper support, that is a reasonable place to start, and a good prescriber will say so. If you have made several and found that hunger defeated you every time, that is precisely the situation these medicines were developed for.

How to choose between UK providers

Most comparison of weight-loss providers happens on price, because price is the only figure most websites make easy to find. It is also the least useful thing to compare, because the medicine is identical and the service is not.

These are the questions worth asking any provider — including this one.

We have published side-by-side comparisons with Boots, MedExpress, VOY, Juniper and Simple Online Pharmacy.

About the pharmacy

• What is your GPhC registration number? Then look it up on the General Pharmaceutical Council register yourself rather than trusting the display
• Who is your superintendent pharmacist? A legitimate pharmacy names them
• Is there a real UK address and a working phone number? Be cautious of any provider contactable only through a web form
• Is the pharmacy NHS-contracted? Not essential, but it indicates a pharmacy operating in regulated community practice rather than online only

About the clinical process

• Who reviews my assessment, and what are they registered with? GMC, GPhC or NMC
• How do you verify identity and weight? A provider that accepts a self-reported figure without check is not protecting you
• What happens if my answers raise a question? The right answer is that someone asks you
• Can you decline to prescribe? Any provider that guarantees approval before assessing you is telling you how seriously it takes the assessment

About ongoing care

• Who decides when my dose increases, and what do they look at?
• Is there a clinical review before each repeat supply, or just a payment?
• Who do I contact when side effects appear, and how quickly do they respond?
• What happens if I plateau?
• What happens if I want to stop?

About the practicalities

• How is cold chain maintained in transit? Injectable treatment requires refrigeration before first use
• Are needles, swabs and a sharps bin included?
• Is this a subscription? Can I cancel? Does the price change after month one?
• What is the total cost at a maintenance dose, including everything?

How to compare pricing fairly

The advertised price is the wrong number. Here is how to work out the right one.

What happens after you are approved

Approval is the start of treatment, not the end of the process. Here is what follows.

1. Your prescription is issued by the reviewing prescriber and dispensed from our registered premises
2. Treatment is dispatched in temperature-controlled packaging where required, with needles and swabs included for injectable treatment
3. You start at the initiation dose — not a treatment dose. This is deliberate, and it is why early weight change is often modest
4. Your first review falls at around four weeks, before any dose decision is made
5. You report honestly at that review. How you tolerated the dose matters more than what you hoped to have lost
6. A dose decision is made — increase, hold, or in some cases step back
7. Each subsequent repeat follows the same check-in
8. You have pharmacist access throughout for anything between reviews

What we will ask you at each review

• Weight change and over what period
• Whether side effects are settling, persisting or worsening
• Any new symptoms, particularly abdominal pain
• Any new medicines started
• Whether your other conditions or medicines need reviewing as your weight changes
• Your eating pattern, protein intake and activity
• Whether the treatment is still doing what you wanted it to

What happens if treatment is declined

Not every assessment results in a prescription, and that is how it should be. Roughly, a decline falls into one of four categories, and they are not equivalent.

Something needs investigating first. Unexplained weight change, abdominal pain or another symptom needs a diagnosis before a weight-management medicine is layered on top. This is usually temporary — treat the symptom, then reassess.

Something needs adjusting first. A medicine that interacts, a condition that needs stabilising, or a diabetes regimen that requires coordination with the team managing it. Also usually temporary.

You do not meet the licensed criteria. If your BMI is below the threshold, no legitimate UK provider will supply treatment, and one that offers to is not one you want.

Remote care is not appropriate for your situation. Some presentations are better managed face to face. This is a judgement about the setting, not about you.

Questions patients forget to ask

These come up constantly at review, and almost never at the point of choosing a provider — by which time they matter most.

“What happens if this dose stops working?” Plateaus are normal and expected. The answer should involve a review of consistency, intake and other factors before any dose change — not an automatic escalation.

“What happens if I need to pause?” Supply issues, cost, travel, illness. Ask whether restarting requires a new assessment and whether you can resume at your previous dose.

“Who do I speak to at 8pm on a Sunday when I feel awful?” Ask what the actual route is, and what the response time is.

“What happens to my other medicines as I lose weight?” Blood pressure medicines in particular commonly need reducing. Ask who is watching for that.

“What is the plan for stopping?” Ask this at the start, not at month fourteen. A provider with no answer has not thought past the repeat order.

“What do you do if I am not losing weight?” The answer should be a structured review, not a higher dose by default.

“Can I speak to the prescriber, or only to customer service?”

How this guide is written and maintained

This page is a clinical resource, and it is maintained like one.

Who writes it

Written by Shadeia Younis, Superintendent Pharmacist (GPhC No. 2052119), with 25 years of clinical pharmacy experience and SCOPE certification in obesity management.

What we cite

In priority order: UK Summaries of Product Characteristics and MHRA-approved Patient Information Leaflets; MHRA safety communications; NICE technology appraisals and guidelines; NHS England commissioning guidance; peer-reviewed publications of the registration trials.

We do not cite blogs, affiliate sites, forums or AI-generated summaries. Where a figure varies between published analyses of the same trial, we say so and give the range rather than picking the most favourable number.

What we do when the evidence is uncertain

We say it is uncertain. The long-term safety section on this page is an example — the class has a long record in diabetes care, weight-management use is more recent, and data beyond a few years is still accumulating. Implying more certainty than exists would make the page more persuasive and less accurate, and we would rather it were accurate.

How often it is updated

Every substantive change is recorded in the change log with the date, the section, the reason and the reviewer.

Corrections

If you believe something on this page is inaccurate or out of date, tell us and we will check it. Corrections to clinical content are made promptly and recorded in the change log rather than edited silently.

What it costs to find out if you qualify

Nothing. The assessment is free and takes about two minutes.

This matters more than it sounds, because the single most common hesitation we hear from people considering treatment is some version of: what if I go through all this, pay, and then get turned down?

Completing an assessment does not guarantee approval — and finding out costs you nothing.

What you are and are not committing to

Worth setting out plainly, because subscription terms and auto-renewals are the most common source of complaint in this market.

Why ongoing clinical support changes the outcome

This is the part of the decision most people underweight, because it is the hardest thing to see from a website.

The medicine is identical between providers. What is not identical is what happens in months two through twelve — and that is where treatment succeeds or falls apart.

None of the situations in the left-hand column is unusual. All of them are routine, and all of them have a good answer if someone is watching.

Monthly clinical reviews are included in our published price rather than sold as an upgrade, and you have direct access to a pharmacist between reviews. That is not a marketing feature — it is what makes the difference between the outcomes in the middle column and the ones on the right.

How to check we are who we say we are

Everything on this page about Slinic is independently verifiable, and we would rather you checked than took our word for it.

Premises registration and individual professional registration are two separate things. Both can be checked, and a provider that displays only one of them is worth a second look.

Frequently asked questions

The basics

Eligibility

NHS access

Cost

Starting treatment

Doses

Side effects and safety

Pregnancy and contraception

Everyday life

Switching and stopping

Change log

Related guides

• Mounjaro UK — complete tirzepatide guide
• Wegovy UK — injection and pill guide
• Wegovy Pill UK — oral semaglutide in detail
• Mounjaro vs Wegovy — head-to-head comparison
• Eligibility guide — NHS cohorts and private criteria
• Provider price comparison — every UK provider compared
• NHS vs private treatment
• Side effects guide — symptom-by-symptom management
• Restarting after a break

References

Primary sources. Every trial publication and current UK guidance document is linked directly.

1. MHRA / GOV.UK — marketing authorisations for tirzepatide, semaglutide and liraglutide products.
2. electronic Medicines Compendium — Mounjaro KwikPen Summary of Product Characteristics.
3. electronic Medicines Compendium — Wegovy FlexTouch Summary of Product Characteristics.
4. electronic Medicines Compendium — liraglutide 6 mg/mL Summary of Product Characteristics.
5. electronic Medicines Compendium — Wegovy 7.2 mg and oral semaglutide Summaries of Product Characteristics (search by product name).
6. MHRA — statement on approval of oral semaglutide for weight management, 11 June 2026.
7. NICE TA1026 — Tirzepatide for managing overweight and obesity.
8. NICE TA875 — Semaglutide for managing overweight and obesity.
9. NICE NG246 — Overweight and obesity management. Published 14 January 2025, last updated 8 January 2026.
10. NHS England — Weight management injections: access and commissioning.
11. Jastreboff AM et al. Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). N Engl J Med 2022;387(3):205–216. doi:10.1056/NEJMoa2206038.
12. Jastreboff AM et al. Tirzepatide for obesity treatment and diabetes prevention — SURMOUNT-1 three-year outcomes. N Engl J Med 2025;392(10):958–971. doi:10.1056/NEJMoa2410819.
13. Aronne LJ et al. Continued treatment with tirzepatide for maintenance of weight reduction (SURMOUNT-4). JAMA 2024;331(1):38–48. doi:10.1001/jama.2023.24945.
14. Aronne LJ et al. Tirzepatide as compared with semaglutide for the treatment of obesity (SURMOUNT-5). N Engl J Med 2025;393(1):26–36. doi:10.1056/NEJMoa2416394.
15. Wilding JPH et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). N Engl J Med 2021;384(11):989–1002. doi:10.1056/NEJMoa2032183.
16. Rubino D et al. Effect of continued weekly subcutaneous semaglutide vs placebo on weight loss maintenance (STEP 4). JAMA 2021;325(14):1414–1425. doi:10.1001/jama.2021.3224.
17. Wharton S et al. Oral semaglutide at a dose of 25 mg in adults with overweight or obesity (OASIS 4). N Engl J Med 2025;393(11):1077–1087. doi:10.1056/NEJMoa2500969.
18. STEP UP — semaglutide 7.2 mg phase 3b trial. Publication reference to be added.
19. SCALE trial programme — liraglutide 3.0 mg. Publication reference to be added.
20. General Pharmaceutical Council — register of registered pharmacies and pharmacy professionals.
21. British National Formulary — tirzepatide, semaglutide, liraglutide.
22. Centre for Perioperative Care — guidance on GLP-1 receptor agonists and anaesthesia.
23. Faculty of Sexual and Reproductive Healthcare — contraception guidance.
24. MHRA Yellow Card scheme — reporting suspected side effects.

All sources accessed 31 July 2026. Where guidance conflicts, current UK product information takes precedence.