How to Get Fat Loss Injections in the UK (October 2026)

01 · The routes

How do you get fat loss injections in the UK?

You get them on prescription, by one of two legitimate routes: the NHS, or a regulated private pharmacy. The main licensed options are Mounjaro (tirzepatide) and Wegovy (semaglutide). Mounjaro is a once-weekly injection made by Eli Lilly, licensed in the UK for weight management in adults.¹

Whichever route you choose, a clinician must first judge whether the medicine suits you. A prescriber assesses your BMI, medical history and current medicines before deciding.¹ That is the line between a genuine supplier and a risky one: genuine treatment always involves a prescription and a clinical consultation.⁷

If you want the full NHS picture first, our guide on whether you can get these injections on the NHS goes through it, and our page on how to get referred for weight loss injections covers what to say to your GP.

02 · NHS or private

NHS or private: which should you choose?

Choose the NHS if you fit its current criteria and can wait; choose private treatment if you meet the licensed criteria but not the NHS ones yet. Mounjaro is available on the NHS, but access is phased in over several years. NICE recommends it for adults with a BMI of at least 35 plus at least one weight-related condition.⁴

The primary-care rollout began in June 2025 with the highest-need groups first, initially BMI 40+ with four or more qualifying conditions.⁶ Full rollout is expected to take years. That is why many people who meet the licensed criteria choose regulated private treatment rather than waiting.⁶ NHS prescriptions in England carry the standard £9.90 charge unless you are exempt, but ask your GP how that applies to this medicine.

The two routes are not exclusive. Some people start privately and move to NHS care when they reach the front of the queue. Tell your GP about any treatment you are taking either way.

03 · Cost

How much do fat loss injections cost?

With us, a Mounjaro pen costs £169.99 per month at the 2.5mg starting dose and rises with the dose. Each pen is four weekly doses, so one pen is one month of treatment. At standard prices the pens cost £189.99 at 5mg, £244.99 at 7.5mg, £274.99 at 10mg, £289.99 at 12.5mg and £299.99 at 15mg.

New customers save £40 on their first order at any dose with code FIRST40. After that, an automatic £25 reorder discount applies to every future order (code DOSE25). If you step up after 4 weeks on each dose, your first four pens (2.5mg to 10mg) cost £879.96 at standard prices. A first year costs £2,399.88 if you stay on 5mg after your 2.5mg starting pen, up to £3,279.88 if you step up through every dose to 15mg, again before discounts.

For context, across the UK pharmacies we track (checked 24 October 2026), Mounjaro pens range from £143.96 to £319.99 per month at standard prices, depending on dose and provider. The cheapest and dearest 2.5mg starting pens run from £143.96 to £179.99. For the same dose, the gap between providers ranges from £20 to £36.03. Our Mounjaro price comparison sets this out in more detail.

The consultation is free and the price shown is the price paid, with no hidden fees. You can pay by Visa or Mastercard, or use Klarna or pay-monthly options. There are no subscriptions.

04 · Ordering

How does ordering work with us?

Ordering takes three steps, and if the prescriber decides the treatment is not suitable, your order is refunded automatically in full.

• Free online consultation. Complete a short health questionnaire, with no charge and no obligation. You can start your free consultation at any time.
• Prescriber review. A GPhC-registered prescriber reviews your answers, not a scoring script. Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full.
• Dispensing and delivery. Our registered pharmacy dispenses your pen. We dispatch the same day when you order by 3pm, with free next-day tracked delivery in discreet, temperature-controlled packaging. Saturday delivery is £14.99.

Needles, a sharps bin and injection guidance come with every order. Our prescribing team handles monthly reviews, dose titration and side-effect support. Repeat orders re-check suitability, and nothing ships automatically. If you want to see the full range first, browse all weight loss treatments.

05 · Who is eligible

Who can get fat loss injections?

Mounjaro is licensed for adults with a BMI of 30 or above, or a BMI between 27 and 30 with at least one weight-related condition.¹ Qualifying conditions include high blood pressure, high cholesterol, obstructive sleep apnoea, cardiovascular disease, prediabetes and type 2 diabetes.¹

It must be used alongside a reduced-calorie diet and increased physical activity.¹¹ The injection is a tool within a plan, not a replacement for one. A prescriber will weigh your BMI, medical history and current medicines before deciding if it is suitable.¹

Meeting a BMI number does not automatically mean you will be prescribed it. The prescriber looks at the whole picture, and some people will be advised against it. That is the purpose of a clinical review. If you are unsure where you stand, the free consultation is the quickest way to find out, with no obligation.

06 · Spotting fake pens

Where should you never buy fat loss jabs?

Never buy them from social media, beauty salons or unverified websites. The MHRA has seized thousands of fake weight-loss pens in the UK and has issued alerts after falsified Mounjaro pens were identified.⁷ Fake pens have caused hospitalisations, and some contained insulin rather than tirzepatide.⁷

Before you buy, check the pharmacy on the GPhC register. Ours is registered under 9012878.¹² Be wary of anyone offering to supply without a consultation or prescription. Genuine treatment always involves both.⁷

Genuine UK stock is supplied through Lilly's official distribution to licensed pharmacies. Every pen carries a batch number and expiry date that can be checked. We source Mounjaro directly through official LillyDirect supply, and all six doses are stocked from 2.5mg to 15mg.

When your pen arrives, it should come cold-chain packaged, and the solution inside should be clear and colourless. Do not use a pen that:

• has been frozen
• looks cloudy or discoloured
• has particles in it
• is past its expiry date
• has been out of the fridge for more than 30 days in use, or has been above 30°C

If anything about the supply or packaging seems wrong, check the pharmacy on the GPhC register and contact it before injecting.¹³ Our guide on whether fat loss injections are safe covers the wider safety picture.

07 · How the dose builds

What happens once you start?

Everyone starts Mounjaro on 2.5mg once a week. This starting dose is about letting your body adjust, not about weight loss itself.¹ After at least 4 weeks the dose increases to 5mg. It can then step up by 2.5mg at a minimum of 4-week intervals (7.5mg, 10mg, 12.5mg) to a maximum of 15mg weekly, depending on how you respond and tolerate it.¹

Many people settle at a maintenance dose of 5mg, 10mg or 15mg. Higher is not automatically better, and your prescriber will guide the pace.¹¹

You inject under the skin once a week, on the same day each week, at any time of day, with or without food. Licensed sites 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. Each KwikPen contains four weekly doses.¹

If you miss a dose, take it as soon as you can within 4 days (96 hours) of the scheduled time. If more than 4 days have passed, skip it and take the next one on your normal day. Never take two doses within 3 days of each other.¹

Store pens in the fridge at 2–8°C and never freeze them. Once in use, a pen can be kept out of the fridge at a temperature not above 30°C for up to 30 days after first use, and must then be thrown away.

08 · Do they work?

Do fat jabs actually work?

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. People on lifestyle changes alone lost 3.1%.² These are trial averages. Individual results vary, and treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.²

At 72 weeks, 85% of participants on 5mg, 89% on 10mg and 91% on 15mg had lost at least 5% of their body weight. Half of participants on 10mg and 57% on 15mg lost at least 20%.²

As a worked example only: for someone starting at 100 kg, 15% is about 15 kg and 20.9% is about 21 kg. Your own result may be higher or lower, because trial averages do not predict an individual outcome. The trial figures describe total body weight, not loss from any single area such as the belly. For more, see our page on whether fat loss injections work.

How does it work? Tirzepatide activates two natural gut-hormone receptors at once, GIP and GLP-1. Together these help regulate appetite, slow how quickly the stomach empties and improve how the body responds to insulin. Most people feel fuller sooner and less hungry between meals, which supports a reduced-calorie diet.¹

09 · Realistic pace

How fast will you lose weight?

Weight loss on Mounjaro is gradual by design, so think in months, not 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.¹¹ The trials measured results at 72 weeks.²

Judge progress by the trend, not individual weigh-ins.

Experiences differ widely in the first weeks. Some people notice appetite change and early loss in week one, while others feel little until a higher dose. Both are normal. Early loss includes water weight, which is another reason to watch the trend. Mild nausea, altered appetite and tiredness in the first days after each injection are the commonest early effects and usually settle.¹¹ 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 or eyes (possible gallbladder problems); or signs of a severe allergic reaction such as swelling of the face or throat and difficulty breathing.

Your prescriber reviews your response. If you have lost less than 5% of your starting weight after 6 months on the highest dose you can tolerate, they will discuss whether continuing or stopping is right for you.¹¹ Our ongoing monthly clinical reviews are built around this.

10 · What to avoid

Shortcuts that are not safe

Self-adjusting your dose, or trying to get more from a pen than it is designed to deliver, is not licensed, and we do not endorse it.

Mounjaro is licensed as a once-weekly medicine, and its blood levels are designed around a 7-day cycle. Talk to your clinical team rather than self-adjusting.¹¹

Each KwikPen is designed and licensed to deliver exactly four weekly doses. Use the pen as designed, then dispose of it.¹

Tablets and supplements are a different category from prescription injections. Our guide to fat loss pills and tablets looks at the evidence, safety and expectations.