Botox Injection for Weight Loss: What to Know in the UK (October 2026)

01 · The short answer

Can you use Botox for weight loss?

If your goal is weight loss with medical support, the better question is which treatments are licensed for it.

02 · What is licensed

The licensed alternative: Mounjaro

Mounjaro is licensed in the UK for weight management in adults. It is a once-weekly pre-filled KwikPen in six strengths from 2.5mg to 15mg.¹ It activates two gut-hormone receptors, GIP and GLP-1, which help regulate appetite and slow how quickly the stomach empties.¹ Most people feel fuller sooner and less hungry between meals.

Trial averages do not predict your own result, and treatment works alongside a reduced-calorie diet and more physical activity.

03 · Getting started

How ordering works

Ordering takes three steps, and the consultation is free. First, complete a short health questionnaire through our free consultation. Second, a GPhC-registered prescriber reviews it, and unsuitable orders are refunded automatically. Third, our registered pharmacy dispenses, with same-day dispatch when ordered by 3pm and free next-day tracked delivery. Your first 2.5mg pen costs £129.99 with code FIRST40 (standard price £169.99). Every later order is £25 off the standard price (code DOSE25).

Related guides: Weight Loss Injections and Botox injections for bladderin weight loss.

04 · Who Mounjaro suits

Who can have Mounjaro for weight loss

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. Examples are high blood pressure, high cholesterol, obstructive sleep apnoea, cardiovascular disease, prediabetes or type 2 diabetes.¹ A prescriber assesses your BMI, medical history and current medicines first.

The NHS also offers Mounjaro, but access is being phased in over several years. NICE recommends it for adults with a BMI of at least 35 plus at least one weight-related condition. The primary-care rollout began in June 2025 with the highest-need groups first, initially BMI 40+ with four or more qualifying conditions.⁴⁶ Many people who meet the licensed criteria choose regulated private treatment rather than wait. See all weight loss treatments for other routes.

05 · Side effects

Side effects to expect with Mounjaro

Most Mounjaro side effects are digestive. The most common, affecting more than 1 in 10 people, are nausea, diarrhoea, vomiting, constipation and abdominal discomfort.¹ They are most likely when starting or increasing a dose, and for most people they ease within days to a few weeks.

In the weight-management trials, nausea affected 24.6% of people on 5mg and 28.0% on 15mg, compared with 8.5% on placebo.¹ get medical help straight away for severe, persistent stomach pain that may spread to your back, or for signs of a severe allergic reaction.¹³ You can report any suspected side effect through the Yellow Card scheme.¹⁹

06 · Other injections

Other weight loss injections

We cover some of them separately, including injections into the stomach area, meso injections and the H2 injection. Whatever you consider, check that the pharmacy is on the GPhC register and that a prescriber reviews you first.

07 · 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