Who prescribes weight loss injections, and how does the process actually work?

Step 1 — Understanding who holds prescribing authority in the UK

Before anything else, it helps to know who is legally allowed to prescribe weight loss injections. The short answer: doctors (GPs and hospital physicians), certain nurse prescribers, and pharmacist Independent Prescribers registered with the General Pharmaceutical Council. That last group matters particularly if you're thinking about an online route, because a GPhC-registered Independent Prescriber working at a regulated pharmacy can issue a private prescription directly, without any referral from your GP.

What none of these professionals can do is prescribe these medicines for anyone they haven't properly assessed. The NHS guidance on tirzepatide makes clear that these are serious medicines with a specific licensed purpose, not something that can change hands on the basis of a brief online form alone. A real clinical assessment (reviewing your weight, medical history, current medications and any relevant conditions) sits at the heart of every legitimate prescription.

If you want a fuller breakdown of which professional titles carry independent prescribing rights, our guide to prescribing authority for weight loss injections goes through each role in more detail.

Step 2, Choosing your route: NHS or private prescriber

Once you know who can prescribe, the next question is which route suits your situation. The NHS route runs through your GP or a specialist weight management clinic. GPs can now prescribe tirzepatide under the 2026 GP contract, though participation is optional and varies by practice and region, so the same medicine that's available in one area may not yet be accessible in another. NHS access to weight loss injections is also subject to strict eligibility criteria, including BMI thresholds and the number of qualifying health conditions you have, which means many people who would benefit clinically don't currently meet the criteria or face long waits.

The private route works differently. A prescriber at a GPhC-registered online pharmacy reviews your consultation independently, without needing involvement from your GP first. That's the model at nume: every consultation is read personally by a GPhC-registered Independent Prescriber (a real clinician, the same day) and a prescription is issued only if treatment is appropriate for you. If you'd like to understand more about this route specifically, our page on getting weight loss injections prescribed online covers how it works in practice.

It's worth being honest with yourself here: if you've already looked into the NHS route and hit a wall, you probably felt more than a little frustrated. That's understandable. Knowing a treatment exists and watching eligibility criteria move around you is genuinely dispiriting.

Step 3, What the assessment covers and why it matters

Whoever prescribes your treatment, the assessment will cover broadly the same ground. Your prescriber needs your current weight, height and BMI; a clear picture of your medical history (particularly any history of pancreatitis, gallbladder disease, thyroid conditions or eating disorders); the medicines you're already taking; and whether you're pregnant, breastfeeding or planning a pregnancy, since these injections are not recommended in those situations. Under-18s are outside the licensed scope of both Mounjaro and Wegovy.

At a GPhC-registered online pharmacy like nume, this assessment also includes photo-ID identity verification and live weight verification via video, alongside a check of any relevant clinical history. Those steps aren't bureaucracy for its own sake, they protect you, and they're part of what separates a genuinely safe service from a seller operating outside the law. You can verify any online pharmacy's registration on the GPhC pharmacy register before sharing any personal or health details.

For a broader look at the eligibility picture, including the BMI thresholds and weight-related conditions that qualify, the prescribed weight loss injection eligibility page covers the licensed criteria for both Mounjaro and Wegovy.

Step 4, What happens after the prescription is issued

A legitimate prescription doesn't just unlock the medicine; it begins an ongoing clinical relationship. Reputable prescribers review your progress before authorising each repeat supply. At a private service, that means your notes are re-read before your next pen is dispensed, not automatically re-sent on a subscription. Dose increases are handled with the same scrutiny, because moving up the titration schedule when the evidence doesn't support it carries real clinical risk.

If cost is a factor in your thinking, our weight loss injection cost guide explains what legitimate private pricing actually includes and why the headline number rarely tells the whole story. For a general overview of the available treatments, the weight loss injections overview page gives a clear summary of Mounjaro and Wegovy side by side.

NICE has appraised both medicines (tirzepatide under TA1026 and semaglutide under TA875) and both appraisals assume prescribing happens within a framework of clinical oversight, dietary support and regular review. That oversight doesn't end with the first pen.