What Can I Take for Weight Loss in the UK? (October 2026)

01 · The core answer

What can you take for weight loss in the UK?

The main options are licensed prescription medicines, prescribed after a proper assessment and used alongside a reduced-calorie diet and increased physical activity. Supplements and over-the-counter pills are not equivalent to licensed medicines, and nothing replaces eating and activity changes.

You can read more in our guide to whether weight loss drugs suit you.

02 · Is it for you?

Should I take Mounjaro for weight loss?

You can take Mounjaro for weight loss if a GPhC-registered prescriber judges it suitable for you after reviewing your health questionnaire. It is a prescription-only medicine, licensed for weight management in adults, and it is used alongside a reduced-calorie diet and increased physical activity.¹

Two practical decisions usually follow. First, are you in a group the NHS can currently treat? NICE recommends Mounjaro for adults with a BMI of at least 35 plus at least one weight-related condition, and the NHS primary-care rollout began in June 2025 with the highest-need groups first. Full rollout is expected to take years.⁴⁶ Second, if you do not want to wait, regulated private treatment is available.

If you are ready to explore it, our weight loss clinic explains the process, and the Mounjaro pen page shows live prices and starts the free consultation. Stock is currently in stock, and our prescribers review every order, so unsuitable requests are refunded automatically.

If you are still unsure, our page on who can take weight loss injections goes through the questions a prescriber will ask.

03 · How to take Mounjaro

How to take Mounjaro for weight loss

You take Mounjaro as an injection under the skin (subcutaneously) once a week, on the same day each week, at any time of day, with or without food.¹ It is not a tablet or a liquid, and you do not take it daily.

The injection sites licensed for tirzepatide are the stomach area (at least 5cm from the belly button), the front of the thigh, or the back of the upper arm if someone else gives the injection. Rotate the site with each dose so you are not injecting the same patch of skin repeatedly.¹³

Each KwikPen contains four weekly doses. You set the dose by turning the knob until the dose indicator shows the correct dose in the window.

Needles, a sharps bin and injection guidance come with every order, and the same guidance is in the patient information leaflet.

04 · How much to take

How much Mounjaro should you take?

Everyone starts on 2.5mg once a week, and your prescriber decides how far to go from there. The starting dose is about letting your body adjust, not about weight loss itself.¹

After at least four weeks the dose increases to 5mg. It can then step up by 2.5mg at a minimum of four-week intervals (7.5mg, 10mg, 12.5mg) up to a maximum of 15mg weekly, depending on how you respond and tolerate it.¹¹¹ The dose you take is therefore the one you have reached on the ladder, not a number you choose in advance.

Many people settle at a maintenance dose of 5mg, 10mg or 15mg. Higher is not automatically better, and your prescriber will guide the right pace.

Tirzepatide is the active ingredient in Mounjaro, which comes in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg. There is no licensed way to take a smaller portion of a pen.

05 · How often, and missed doses

How often do you take Mounjaro?

You take Mounjaro once a week, on the same day each week. There is no best time of day: it works the same morning or evening, with or without food. What matters is the same day each week.¹ Pick a day and time you will remember. Many people choose a weekend morning so early side effects fall on days off.

Taking it more often than weekly is not allowed under the licence, and the dose should only go up at the pace your prescriber sets, no faster than after at least four weeks.

If you forget, the rule is simple. If you miss a dose, take it as soon as you can within 4 days (96 hours) of the scheduled time, then carry on with your usual day. If more than 4 days have passed, skip the missed dose entirely and take the next one on your normal day — never take two doses within 3 days of each other.¹

You can also change your weekly injection day if needed, as long as at least 3 days (72 hours) have passed since your last dose.¹ Our ongoing monthly clinical reviews are a good moment to raise any difficulty with your routine.

06 · What results to expect

What results can you realistically expect?

Weight loss on Mounjaro is gradual by design, and results build over months rather than days. The first weeks on 2.5mg are an adjustment phase and losses are usually modest. Most measurable progress builds from 5mg onward, month by month.¹

The headline trial is SURMOUNT-1. In the SURMOUNT-1 trial of 2,539 adults, people taking tirzepatide alongside diet and exercise lost on average 15% of their body weight on 5mg, 19.5% on 10mg and 20.9% on 15mg over 72 weeks, compared with 3.1% with lifestyle changes alone.² These are trial averages. Individual results vary, and treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.

As a worked example only, for someone starting at 100 kg, 20.9% is about 21 kg. Your own result depends on your starting point, your dose, your diet and how you tolerate treatment.

Early loss includes water weight, so the trend over weeks matters more than any single weigh-in. Some people notice appetite change and early loss in week one, others feel little until a higher dose, and both are normal. Mild nausea, altered appetite and tiredness in the first days after each injection are the commonest early effects and usually settle.¹

Your response is also reviewed. If you have lost less than 5% of your starting weight after 6 months on the highest dose you can tolerate, your prescriber will discuss whether continuing or stopping is right for you. To see how progress typically shapes up, read our explainer on the Mounjaro weight loss curve.

07 · Pills, drinks and supplements

What about over-the-counter pills, drinks and supplements?

Over-the-counter weight loss pills are not equivalent to licensed prescription medicines, and for many products there is no good evidence at all. Low-cost supplements are available cheaply without assessment, which is exactly why caution matters.

Berberine, so-called 'nature's Ozempic', fibre capsules, fat burners and herbal teas are the products most often promoted. They are not equivalent to a GLP-1 medicine, they have no clinical oversight, and their dosing is not standardised.

Treat dramatic weight-loss claims as a warning sign. Be especially wary of anyone offering to supply a prescription injection without a consultation or prescription: counterfeit and unlicensed pens are a real risk, and the MHRA publishes alerts about them. Check any online pharmacy on the GPhC register; ours is GPhC 9012878.

If you take any supplement and feel unwell, speak to a pharmacist or your GP. Suspected side effects of any medicine can be reported through the MHRA Yellow Card scheme.¹⁹

08 · Quick fixes and fat-burning myths

Is there anything that burns fat extremely fast?

No food, drink or pill burns fat extremely fast in a safe, lasting way. Questions such as which drink burns the most belly fat, or what the laziest way to burn fat is, have the same honest answer: there is no shortcut, and you cannot choose where on your body fat comes off.

What does work is a sustained reduced-calorie diet, more physical activity, and, for people who qualify, a medicine that makes that diet easier to follow. Tirzepatide helps regulate appetite and slows how quickly the stomach empties, so most people feel fuller sooner and less hungry between meals, which supports a reduced-calorie diet.¹

Wanting to lose a lot of weight quickly is understandable, but in the SURMOUNT-1 trial results were measured at 72 weeks, not days. Think in months, and judge progress by trend. If you are aiming at a specific event, talk to a prescriber about a realistic plan rather than a crash approach.

Weight is influenced by many things, including sleep, stress, medicines and health conditions, and a prescriber or GP can help you look at your own situation rather than relying on a generic answer.

09 · Safety and interactions

Safety checks before you start

Before taking any weight loss medicine, tell the prescriber about every medicine you use. Tirzepatide can reduce the absorption of oral contraceptives because stomach emptying slows. The SmPC advises switching to a non-oral method, or adding a barrier method (such as condoms), for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase.¹ If you use insulin or sulfonylureas, doses may need adjusting because of the risk of low blood sugar.

Our pages cover ibuprofen alongside Mounjaro, codeine alongside Mounjaro and methotrexate with weight loss injections. Always confirm with your prescriber or pharmacist for your own circumstances.

Report any suspected side effect through the Yellow Card scheme.¹⁹ Mounjaro is a prescription-only medicine, supplied only after an online consultation reviewed by a GPhC-registered prescriber. Individual results vary, and this page is information, not a substitute for medical advice.

10 · Serious side effects

Serious side effects: when to get help straight away

Serious side effects are uncommon but need urgent attention. Seek immediate medical help for: severe, persistent stomach pain that may spread to your back, with or without vomiting (possible pancreatitis); pain in the upper right abdomen, fever or yellowing of skin/eyes (possible gallbladder problems); or signs of a severe allergic reaction such as swelling of the face or throat and difficulty breathing. If you take insulin or a sulfonylurea alongside Mounjaro, watch for low blood sugar (shakiness, sweating, confusion) — your prescriber may need to adjust those medicines.¹

11 · Storage, travel and ordering

Storing your pen and getting started

Keep Mounjaro pens in a fridge at 2–8°C and never freeze them. Once in use, a pen can be kept out of the fridge not above 30°C for up to 30 days, useful for short trips, after which it should be discarded. Keep the pen cap on to protect it from light, and never use a pen that has been frozen.¹

You can fly with Mounjaro. Carry pens in hand luggage, because hold luggage can fall below freezing, ideally in a cool bag with the prescription label or a copy of your prescription. Unopened pens should stay in the fridge until the expiry date printed on the box. If an unopened pen has been out of the fridge, check with the pharmacy before using it.¹³

Ordering with us works in a few steps. Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full. We dispense from our registered pharmacy, with same-day dispatch when ordered by 3pm, and free next-day tracked delivery in temperature-controlled packaging. Mounjaro comes through official LillyDirect supply, and ongoing monthly reviews are included. New customers save £40 on their first order with code FIRST40, and an automatic £25 reorder discount applies to every future order (code DOSE25).

Our note on Manjura weight loss clarifies a product name people often mistype.