GLP-1 Weight Loss Injections UK: Complete Guide (2026)

What are GLP-1 weight loss injections? GLP-1 receptor agonists are a class of prescription medications that help you lose weight by reducing appetite and slowing digestion. Originally developed for type 2 diabetes, they are now widely prescribed for weight management in the UK. This guide covers everything you need to know.

Which GLP-1 injections are available in the UK?

| Medication | Active ingredient | Dose | Frequency | Licensed for weight loss? | |-----------|-------------------|------|-----------|--------------------------| | Mounjaro | Tirzepatide | 2.5–15mg | Weekly | Yes | | Wegovy | Semaglutide | 0.25–2.4mg | Weekly | Yes | | Ozempic | Semaglutide | 0.25–1mg | Weekly | No (diabetes only, used off-label) | | Nevolat | Liraglutide | 0.6–3mg | Daily | Yes (replaced Saxenda) | | Rybelsus | Semaglutide | 3–14mg | Daily tablet | No (diabetes, used off-label) |

How do GLP-1 injections work?

GLP-1 (glucagon-like peptide-1) is a hormone your body naturally produces after eating. GLP-1 medications mimic this hormone at much higher levels, which:

1. Reduces appetite — you feel full sooner and stay full longer
2. Slows gastric emptying — food moves through your stomach more slowly
3. Regulates blood sugar — reduces insulin spikes that drive hunger
4. Changes food reward signals — many patients report reduced cravings

Mounjaro also activates a second receptor (GIP), which is why it's sometimes called a "twincretin." This dual action is believed to explain its superior weight loss results.

Who is eligible?

GLP-1 medications are prescribed for adults with:

• BMI of 30 or above (clinically obese), or
• BMI of 27 or above with at least one weight-related condition (type 2 diabetes, high blood pressure, high cholesterol, sleep apnoea)

A clinical consultation is required before prescribing. Most UK private providers include this in their price or charge a separate consultation fee.

How much do GLP-1 injections cost?

Prices vary significantly between providers. Here are typical weekly costs:

| Medication | Starter dose | Maintenance dose | |-----------|-------------|-----------------| | Mounjaro | From £29.75/week | £40–60/week | | Wegovy | £35–50/week | £50–70/week | | Ozempic | £30–50/week | £40–55/week | | Nevolat | £20–40/week | £30–50/week |

How much weight can you lose?

Results from major clinical trials:

| Medication | Trial | Average weight loss | Duration | |-----------|-------|-------------------|----------| | Mounjaro 15mg | SURMOUNT-1 | 22.5% of body weight | 72 weeks | | Wegovy 2.4mg | STEP 1 | 15% of body weight | 68 weeks | | Ozempic 1mg | STEP 2 | 9.6% of body weight | 68 weeks | | Nevolat 3mg | SCALE | 8% of body weight | 56 weeks |

For a person weighing 100kg, that translates to approximately 22.5kg with Mounjaro, 15kg with Wegovy, or 8kg with Nevolat.

NHS vs private

NHS: Wegovy and Mounjaro are available through NHS specialist weight management services, but waiting lists are typically 6–18 months and not all areas offer them. Access criteria are strict.

Private: Available from GPhC-registered online pharmacies and CQC-regulated clinics. You can start within days of your consultation. Prices are updated daily on Treatcompare.

The vast majority of UK patients currently access GLP-1 medications privately due to NHS waiting times.

How to choose a provider

1. Check registration — the provider should be GPhC-registered (pharmacy) or CQC-regulated (clinic)
2. Compare total cost — including consultation, monitoring, and any extras
3. Check what is included — some providers include ongoing prescriber access; others don't
4. Read reviews — patient reviews can highlight the quality of clinical support

Frequently asked questions

Are GLP-1 injections safe? Yes, when prescribed by a qualified clinician. They have been extensively studied in clinical trials with thousands of participants. Common side effects are gastrointestinal (nausea, diarrhoea) and usually settle within weeks.

Do I need to inject myself? Yes, but the injection pens are pre-filled and designed for self-administration. Most patients find the injection virtually painless after the first time.

What happens when I stop? Weight regain is common if you stop without maintaining lifestyle changes. Discuss a long-term plan with your prescriber.

Can I take GLP-1 medications with other drugs? Tell your prescriber about all medications you take. GLP-1 medications can interact with insulin and some diabetes drugs.

Related guides

• Mounjaro vs Wegovy: Which Is Better? — head-to-head comparison
• Mounjaro vs Wegovy Side Effects — side effect comparison
• GLP-1 Weight Loss Injections: Complete Guide — all options explained
• Nevolat: The Saxenda Replacement — daily injection guide
• Ozempic vs Wegovy — same drug, different doses