GLP-1 receptor agonists
Semaglutide, liraglutide and orforglipron act on the GLP-1 receptor. Their formulations and approved uses differ; the medicine's name alone does not tell you its full indication.
A guide to what these medicines do, why clinical review matters and the safety information to discuss with your prescriber.
Read the guideGLP-1 stands for glucagon-like peptide-1. GLP-1 receptor agonists act on a hormone pathway involved in appetite and blood-sugar regulation. They can reduce appetite and help people feel full for longer.
Some medicines are used for type 2 diabetes; certain products are also licensed for weight management. The approved use depends on the specific product.
Further reading: NHS medicine information.
Medicines in this area are not interchangeable. A prescriber must consider the particular product, its licensed use and your health.
Semaglutide, liraglutide and orforglipron act on the GLP-1 receptor. Their formulations and approved uses differ; the medicine's name alone does not tell you its full indication.
Tirzepatide acts on both GLP-1 and GIP receptors. It is a distinct medicine, with its own instructions, precautions and prescribing requirements.
Brand, formulation and licensed indication matter. Your prescription and patient leaflet explain how your particular medicine should be used.
| Medicine / formulation | Receptor activity | Usual frequency | Important distinction |
|---|---|---|---|
| Semaglutide injection | GLP-1 | Once weekly | Wegovy has a weight-management indication; Ozempic is a diabetes product. Indications depend on the exact product. |
| Semaglutide tablet | GLP-1 | Once daily | Wegovy tablets were authorised for weight management on 11 June 2026. Rybelsus is a different tablet product used for type 2 diabetes. |
| Liraglutide injection | GLP-1 | Once daily | Some products are for weight management, others for diabetes. Check the specific prescription and leaflet. |
| Tirzepatide injection | GLP-1 and GIP | Once weekly | The UK product Mounjaro has indications for type 2 diabetes and weight management in eligible patients. |
| Orforglipron tablet | GLP-1 | Once daily | Foundayo was authorised in the UK for weight management and type 2 diabetes on 10 August 2026. |
On smaller screens, swipe across the table. This is an information comparison, not a prescribing guide or Valixe product catalogue.
Authorisation does not mean universal availability. UK approval, NHS access, pharmacy stock and Valixe's service offering are separate matters. A doctor must still decide whether a particular medicine is suitable.
Sources: NHS semaglutide, NHS liraglutide, NHS tirzepatide and the MHRA announcements for Wegovy tablets and orforglipron.
The route is one part of the decision. Formulation, administration instructions, licensed use and individual risks all matter.
Semaglutide and tirzepatide injections are usually weekly; liraglutide injections are daily. Patients need to understand the device, storage and safe disposal instructions for their product.
The prescribed dose and any increases must follow the treatment plan. Daily and weekly schedules are not interchangeable.
Oral semaglutide requires an empty stomach after at least eight hours of fasting, a small amount of water, and a wait of at least 30 minutes before food or drink. Follow the exact leaflet, including timing of other tablets.
Orforglipron is taken daily without food or water restrictions. This does not remove the need for a prescription, monitoring or attention to side effects.
A tablet is not automatically safer, weaker or more suitable. Do not compare milligram amounts between products or switch between tablets and injections yourself. Different formulations require product-specific advice.
Further reading: MHRA oral semaglutide information, MHRA orforglipron information and the NHS medicine pages below.
Retatrutide is an investigational medicine acting on GLP-1, GIP and glucagon receptors. It is being studied as a once-weekly injection. This triple activity distinguishes it from GLP-1-only medicines and dual GLP-1/GIP medicines.
More receptor targets do not, by themselves, establish a medicine as better or suitable for an individual.
Lilly's Phase 3 TRIUMPH programme evaluates safety and efficacy in defined patient groups. TRIUMPH-1 studied people with obesity or overweight without diabetes; TRIUMPH-2 included type 2 diabetes; TRIUMPH-3 included established cardiovascular disease.
The sponsor has reported results from these trials. These announcements need to be read alongside the study design, full evidence and safety findings; they are not regulatory approval.
Retatrutide is currently not authorised for use in the UK. The MHRA warns against products sold online claiming to contain retatrutide: their contents and quality cannot be relied on. Participation in an authorised clinical trial is different from buying a product from a seller.
Results from separate trials cannot establish which medicine is best: participants, doses, follow-up periods and analyses can differ. This page does not turn trial averages into predicted personal results or give an approval date.
Research and status checked: 9 October 2026. Sources: Lilly's TRIUMPH programme information and the MHRA warning.
Weight-management medicines are normally used alongside changes to eating habits and physical activity. Other support or treatments may be more appropriate.
Clinical suitability depends on factors such as BMI, weight-related conditions, medical history and other medicines. Completing an assessment does not guarantee a prescription.
Further reading: NHS weight-management guidance.
Your assessment is reviewed by a doctor, who may ask for more information before making a decision. The in-house care team coordinates support; prescribing decisions remain with the doctor.
If treatment is approved, the agreed order details and cost are confirmed before payment. The partner pharmacy handles dispensing and dispatch. Ongoing or repeat treatment remains subject to review.
Not everyone experiences side effects, and risks differ between products. Read the full patient leaflet and discuss concerns with your prescriber or pharmacist.
Nausea, vomiting, diarrhoea, constipation and stomach discomfort can occur. Speak to a pharmacist or prescriber if symptoms persist or affect your ability to eat or drink.
Serious reactions can include pancreatitis or an allergic reaction. Some products can also cause gallbladder problems. Low blood sugar is more likely when used with certain diabetes medicines.
Do not wait for a Valixe account message to be answered in an emergency. Account messages and aftercare requests are not emergency services.
Further reading: NHS semaglutide information, NHS tirzepatide information and the MHRA pancreatitis warning.
GLP-1 medicines should not be used during pregnancy, while trying to conceive or while breastfeeding. Discuss pregnancy plans in advance: stopping intervals vary by medicine.
If you take tirzepatide and use the contraceptive pill, add a barrier method or switch to non-oral contraception for four weeks after starting and for four weeks after each dose increase. Discuss your method with a healthcare professional. If pregnancy is suspected, contact your prescriber promptly.
Tell your prescriber about all medicines and supplements, previous pancreatitis and other health conditions. Before surgery or a procedure involving sedation or general anaesthesia, tell the team that you use a GLP-1 medicine. They will advise how to manage it.
Keep your health information up to date. New symptoms or changes to other medicines may affect the treatment plan.
Further reading: MHRA patient safety guidance.
Obtain prescription medicines through a legitimate pharmacy after clinical assessment. Avoid social-media sellers or anyone supplying them without a prescription.
Do not change your dose or switch products on your own. Missed-dose, storage and administration instructions vary: check your leaflet and ask your pharmacist if unsure.
Discuss continuation or stopping with your prescriber, especially if you have diabetes. A longer-term plan should include support for maintaining healthy habits.
You can report a suspected medicine side effect through the MHRA Yellow Card scheme (opens in a new tab). Reporting does not replace getting medical help.
Use your private patient account for non-urgent questions and aftercare requests. The care team can coordinate follow-up with the doctor or pharmacy when needed.
For urgent symptoms, use NHS 111 or emergency services as appropriate.
This guide provides general information and does not replace your patient leaflet or personalised advice. Sources checked on 9 October 2026.