Weight-loss medications in the UK: the complete 2026 guide

If you are looking into weight loss medication in the UK, you are choosing between a small, well-defined set of licensed options — not a sprawling market. This guide sets them all out in one place: what each medicine is, how they compare on results, what they cost across regulated providers, and who can actually get a prescription. Every price below comes from our own tracked data, last checked on 4 July 2026.

There are three prescription treatments most people mean when they search for weight-loss medication today: Mounjaro (tirzepatide, a weekly injection), Wegovy (semaglutide, a weekly injection), and the newer Wegovy Pill (oral semaglutide, a daily tablet). All three are GLP-1-based medicines that work on appetite. The rest of this guide compares them properly.

The three UK weight loss medications, side by side

Each medicine belongs to the same broad family — GLP-1 receptor agonists — but they differ in how they are taken and how much weight people lose on average in the clinical trials.

Mounjaro (tirzepatide) is the only dual-hormone jab, acting on both GIP and GLP-1 receptors. It is taken once a week and, in the SURMOUNT-1 trial, produced average weight loss of around 21% at the top dose. In the SURMOUNT-5 head-to-head study it out-performed semaglutide (roughly 20% versus 14%).

Wegovy (semaglutide) is the most widely used dedicated weight-loss injection. In the STEP 1 trial, participants lost around 15% of their body weight on average. It is also the only one of the three shown to cut heart attack and stroke risk in people with existing heart disease (the SELECT trial).

Wegovy Pill (oral semaglutide) is the UK's first needle-free GLP-1. It is a daily tablet taken on an empty stomach, with results close to the weekly semaglutide jab — the obvious choice for anyone who would rather avoid injections.

For a fuller breakdown of the trade-offs, see our dedicated guide on weight-loss injections versus tablets.

How much does weight loss medication cost in the UK?

Prices vary a lot between providers, and the starter month is often discounted. The table below shows the starting dose of each medicine at our recommended provider, The Weight Clinic, alongside the cheapest ongoing price we currently track across all 24 providers in our data.

*First-month price at The Weight Clinic includes the £35-off NEWME code. Prices are per four weeks at the starter dose and were last checked on 4 July 2026 — always confirm the current price on the provider's own site.

Two things are worth noticing. First, the starter dose is cheap, but the price rises as you step up to a maintenance dose — so the ongoing figure matters more than the first month. Second, the same medicine at the same dose can differ by £80 or more between providers. We break the full spread down in weight-loss medication costs compared across 24 providers, and for the pen-versus-pill question specifically, see Wegovy injection vs Wegovy pill costs.

Who can get weight loss medication in the UK?

These are prescription-only medicines, so a clinician decides. As a general rule, private providers follow criteria in line with NICE guidance (TA1026 for tirzepatide): typically a body mass index (BMI) of 30 or above, or 27 and above if you also have a weight-related health condition such as type 2 diabetes, high blood pressure or sleep apnoea. Lower thresholds may apply for some ethnic backgrounds.

You will normally complete an online consultation covering your height and weight, medical history and current medicines. A prescriber reviews it and may ask follow-up questions. Being outside the criteria — or having a condition that makes the medicine unsafe for you — means you will not be prescribed it, which is exactly why a refund-if-declined policy is useful. Our full walkthrough is in weight-loss medication eligibility in the UK.

Injection or tablet — which should you choose?

There is no single right answer. The weekly injections (Mounjaro and Wegovy) have the longest track record and, for Mounjaro, the largest average results. The daily tablet suits people who dislike needles or want to avoid cold-chain deliveries, at the cost of a stricter routine — an empty stomach and a 30-minute wait before eating.

Whichever route appeals, start by comparing live prices on our homepage master table, which ranks every tracked provider by ongoing cost and pins our recommended pharmacy at the top.

What to watch out for

Only ever buy from a regulated UK provider — a GPhC-registered pharmacy or a CQC-regulated service. Avoid anything sold without a consultation, and steer well clear of "compounded" or unlicensed versions offered online; they sit outside UK regulation and are not the same as the licensed medicines above. All three treatments carry side effects, most commonly nausea, and are not suitable for everyone. Report any suspected side effect through the MHRA Yellow Card scheme.

Frequently asked questions