How To Find The Best GLP-1 Medication For Weight Loss In The UK

GLP-1 drugs are prescription-only medications and should only be obtained following the appropriate medical assessment. Eligibility can vary between providers. Show more Show less Weight loss drugs such as Ozempic, Mounjaro and Wegovy have found their way firmly into the British vernacular over the last few years - but these are all just brands of a type of drug known as GLP-1. An estimated 1.6 million adults in Great Britian used GLP-1s in the year to 2025 meaning the market is awash with options - and this can make researching the best one for you feel overwhelming. We explore how to find the best GLP-1 for your needs, the choice of GLP-1 suppliers in the UK (and eligibility criteria), the potential effectiveness (and side effects) of the drugs - and how to factor the considerable ongoing cost into your monthly budget. What are GLP-1 medications? GLP-1, or its full name GLP-1RA, stands for glucagon-like peptide-1 receptor agonists. These medicines mimic a natural hormone that is released after eating, which makes you feel fuller for longer. Mounjaro, one of the newer GLP-1 drugs, also mimics another appetite-regulating hormone called GIP (glucose-dependent insulinotropic polypeptide). As it works in two ways, it's classed as a 'dual agonist'. GLP-1s come as a pre-measured doses in a single-use injector pen which must be administered as a weekly injection into your, stomach, upper arm, or thigh. Pro Tip In the UK, Ozempic is licensed exclusively for treating type 2 diabetes. It is not prescribed by the NHS for weight management purposes. Some private doctors may prescribe Ozempic 'off-label' any reputable GLP-1 supplier should not offer it Low doses of GLP-1 are usually prescribed for the first four weeks to give your body a chance to adapt to the drug - after which time they can be increased according to advice. It usually takes between two and four weeks of using GLP-1s to start losing weight. Once you've reached your target weight, you can either go onto a lower dose or stop taking the medication. In the UK, the government's Medicines and Healthcare products Regulatory Agency (MHRA) licenses the following GLP-1s: * semaglutide (branded as Wegovy, Ozempic and Rybelsus) * tirzepatide (branded as Mounjaro) * liraglutide (various brand names including Nevolat - the effective equivalent to Saxenda which is no longer being manufactured - and Victoza). However, these drugs have only been approved as 'safe and effective' for patients with obesity and/or weight-related conditions such as cardiovascular disease - and in conjunction with exercise and a healthy diet. It means they may not be safe for people who are already at a healthy weight. Types of GLP-1 medications for weight loss In the UK, Wegovy (semaglutide), Mounjaro (tirzepatide), and Nevolat (liraglutide), are the only GLP-1RA products licensed specifically for weight loss. Ozempic is licensed only to treat type 2 diabetes. However, doctors can use their medical discretion to prescribe the drug for weight loss where they assess the benefits to outweigh the risks - something known as 'off-label'. As a starting point, the table below shoes the brand, type of GLP-1, ingredient, what it's licensed for, and how often it should be taken. BRAND NAME DRUG TYPE ACTIVE INGREDIENT LICENSED USE IN UK FREQUENCY Wegovy GLP-1 Semaglutide Weight loss Weekly Mounjaro GLP-1 and GIP* Tirzepatide Weight loss Weekly Nevolat (Saxenda) GLP-1 Liraglutide Weight loss Daily Ozempic GLP-1 Semaglutide Diabetes (can be prescribed 'off label' for weight loss) Weekly Again, in all cases it's important to note that any weight loss drug will be also be prescribed in combination with a healthy diet and regular exercise. Which GLP-1 is most effective for weight loss? With weight loss drugs falling into one of two main camps (tirzepatide or semaglutide), a common question among researchers into GLP-1s is which of them is most effective for weight loss? While this has been a hotly-debated topic for several years, a medical paper published in May 2026 by the US-based New England Journal of Medicine has offered some clarification. It carried out a study of 751 people with obesity (average weight of around 18 stone/114.3kg) with at least one obesity-related health problem (such as high blood pressure) but who did not have diabetes. Participants were asked to inject the maximum dose of either tirzepatide or semaglutide that they could tolerate every week for a period of 72 weeks. Researchers found that tirzepatide (Mounjaro) reduced body weight by an average of 20.2% compared to Wegovy, which reduced it by 13.7%. Participants on tirzepatide also saw their waist sizes shrink around two inches more on average than those who had taken semaglutide. This would suggest that Mounjaro was the best drug for weight loss. However, the British Heart Foundation points out that, while the study was peer-reviewed and published in a reputable journal, it did not include liraglutide (see our table above), which is available on the NHS under the brand name Nevolat. Participants were also aware which GLP-1 they were taking, which meant it was not a blind study and therefore potentially not as reliable, said the charity. Our findings show that an estimated 4.9 million adults in Great Britain - nearly one in 10 - have recently used a drug to support weight loss or were interested in using one in the near future. This usage far exceeds NHS England's initial goal of prescribing these drugs to 220,000 people over three years. - Professor Sarah Jackson, lead author at the UCL Institute of Epidemiology & Health Care GLP-1 side effects and risks As with any drug, GLP-1s can cause potential side effects on users. These might include nausea, vomiting, diarrhoea and constipation, according to UK government guidance aimed at healthcare professionals. There is nothing to suggest that the type of GLP-1 you take is more or less likely to cause side effects, however. Researchers at New England Journal of Medicine found that a similar number of patients (between 77% and 79%) taking tirzepatide or semaglutide experienced at least one side effect - most commonly digestive problems such as feeling sick, constipation or diarrhoea. Anyone taking these drugs is always advised to read the instructions for use in the patient information leaflet. Do not exceed the prescribed dose, and if you feel unwell, contact your doctor. You can also stop taking GLP-1s at any time. Who qualifies for GLP-1 medications in the UK? However, just understanding what's in GLP-1 medication and the potential risks involved doesn't mean you will officially qualify to get it. Here's what you need to know about eligibility. GLP-1s on the NHS If you are seeking weight loss drugs from the NHS, eligibility will depend on your BMI (body mass index), the criteria for which is set by the National Institute for Health and Care Excellence (NICE). The table below from NICE shows what body mass index and/or weight-related conditions you will need for an NHS prescription by GLP-1 drug type. DRUG BRAND NHS CRITERIA* Tirzepatide Mounjaro Initial BMI of at least 35 and at least one weight-related comorbidity Semaglutide Wegovy, Ozempic and Rybelsus Initial BMI of 35 or more and at least one weight-related comorbidity or initial BMI of 30 to 34.9 and referral to specialist overweight and obesity management services liraglutide Nevolat and Victoza Initial BMI of 35 or more and non-diabetic hyperglycaemia and a high risk of cardiovascular disease *BMI thresholds are usually reduced by 2.5 for people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean ethnic backgrounds. GLP-1s are medicines licensed to treat specific medical disorders and should only be used if you are overweight or diabetic, and not if you want to lose weight for aesthetic or cosmetic purposes - Medicines and Healthcare products Regulatory Agency GLP-1 on private prescription However, according to consumer group Which? only around 5% of those who use weight loss drugs have obtained them through the NHS, with the vast majority accessing them via private prescription at online pharmacies. In the UK, these include trusted high street names such as Asda Online Doctor, Boots Online Doctor, Lloyds Pharmacy Online Doctor, Superdrug Online Doctor, and Well Pharmacy. However, there is also a raft of smaller and lesser-known suppliers. Compared to the NHS, eligibility criteria (namely minimum required BMI) is slightly more relaxed when you obtain GLP-1s privately. That said, in 2025, the General Pharmaceutical Council (GPhC) tightened up rules around qualification, which means you'll now need to supply online GLP-1 providers with evidence of your weight loss requirements. The supplier is now likely to ask for your consent to access your GP medical records for example, while you may also be required to upload photo or video evidence of your current weight such as by standing on the scales. The table below outlines the eligibility criteria for five major online pharmacies in the UK. We've also included what you can expect from the assessment process, and the starting costs for a months' supply of the available injections. PROVIDER ELIGIBILITY CRITERIA* ASSESSMENT PROCESS COST OF MONTHS' SUPPLY (0.25MG INJECTION) Asda Online Doctor BMI of over 30 (or 27 or more if with weight-related health condition) * Fill in online form * Submit GP details * Assessment & prescription issued if suitable Mounjaro (tirzepatide) £148.97 Wegovy (semaglutide) £88.97 Nevolat (liraglutide) £94.97 (3 pack) Boots Online Doctor Unspecified (assessed as part of online application) * Fill in online form * Submit GP details * Assessment & prescription issued if suitable Mounjaro (tirzepatide) £176.97 Wegovy (semaglutide) £79.97 Nevolat (liraglutide) £140.40 (3 pack) Lloyds Pharmacy Online Doctor BMI of over 30 (or 27 to 30 with a weight-related risk factor) * Online consultation which includes uploading video evidence of weight * Assessment & prescription issued if suitable Mounjaro (tirzepatide) £179.99 Wegovy (semaglutide) £99.99 Nevolat (liraglutide) Not available Superdrug Online Doctor BMI of at least 30 (or 27 or more with a weight-related health condition) * Online questionnaire which involves verifying BMI with full-body photos and weight on scales * Camera tool BMI check * Assessment & prescription issued if suitable Mounjaro (tirzepatide) £176 (new patient price with code) Wegovy (semaglutide) £69 (new patient price with code) Nevolat (liraglutide) £175 (3 pack) Well Pharmacy BMI of 30 or over (or over 27 with weight-related health condition) * Online questionnaire which involves video consultation * Assessment & prescription issued if suitable Mounjaro (tirzepatide) £149 Wegovy (semaglutide) £89 Nevolat (liraglutide) £89 (3 pack) *BMI thresholds are slightly reduced for people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean ethnic backgrounds. Are there over-the-counter GLP-1 options? There are no legitimate 'over-the-counter' options for GLP-1 medicine. Buying GLP-1 privately must involve a consultation with a healthcare professional who carries out appropriate checks and ensures you are aware of the benefits and risks of taking the medicine. If you are using a GLP-1 supplier that's outside one of the big names, it's especially important to carry out independent due diligence by checking that it's registered with the GPhC. Its GPhC registration number and logo should be clearly set out on the website's homepage or in the 'about us' section. It's also quick and easy to enter the name of the supplier into the GPhC's online register. Using unregulated injectable medicines could pose a serious risk to your health. Can GLP-1 medications be used long-term? Weight loss medications are largely designed for long-term use, where medically appropriate. However, once a desired weight has been reached, many people prefer to come off the drug and continue their weight management with a combination of diet and exercise. How much do GLP-1 medications cost? While Ozempic is only available for treatment of type 2 diabetes and therefore not available to buy from online pharmacies for weight loss, Wegovy and Mounjaro can be purchased with a private prescription - but, as our table above demonstrates - it's not cheap. Prices for Wegovy's 0.25mg starting dose start at around £100 for a four-week supply, for example, while the highest dose at 2.4mg can start at around £240. Mounjaro is more expensive still, with prices starting at around £150 for a four-week supply of the lowest 2.5mg dose, rising to more than £315 for the equivalent supply of the 15mg dose. Especially for long-term use, it means that costs can very quickly stack up. While prices between pharmacies vary, you should regard unusually low costs as a major red flag, and always cross-reference the supplier against the GPhC's online register. Some private GLP-1 suppliers offer monthly payment plans but be wary what you sign up to and check interest rates. It's best to avoid getting into any debt at all but if you plan to borrow for your weight loss management, set up a clear repayment timescale and schedule. You could consider a purchase credit card that offers an initial interest-free period, for example. Consider all other options before committing to a monthly cost for weight loss drugs that your regular budget cannot absorb. Can GLP-1s be taken orally in the UK? Rybelsus (a semaglutide like Wegovy and Ozempic) is the only GLP-1 medication licensed for oral use. However, it is not currently licensed for weight loss purposes in the UK. The US has a Wegovy tablet which is not available in the UK yet - but could be soon. Switching between GLP-1 medications After carrying out your research and settling into an initial period of the right GLP-1 for you, it may be that your weight loss begins to plateau. In this case, if your doses cannot be increased, you might want to consider switching medication as one of several options. However, before making the jump from one GLP-1 medicine to another, consult your doctor or healthcare professional for advice - even if you are switching between brands that contain the same type of GLP-1. Switching without medical advice could increase the risk of side effects and/or make the treatment less effective. Alternatives to GLP-1 There are no natural alternatives that mimic the natural 'feeling full' hormone in the same way that GLP-1 drugs do. There are prescription weight loss pills however, including Orlistat and MySimba which are often available from the same online providers. You can also choose to focus on the right foods that will keep you feeling fuller for longer. This means healthy proteins such as eggs, lean meats, fish, and nuts and seeds, and good fats such as olive oil. Cut right down on high fat or sugary foods that create slumps and hunger cravings, and eat plenty of fruit and vegetables. Reduce the number of calories you eat with a view to trying to lose weight steadily - the NHS recommends between one to two pounds a week, for example. Reduce your alcohol intake, which is high in sugar calories, and try to be active for between 45 and 60 minutes a day. Most importantly, give yourself time and a good dose of kindness on your journey.