Factual patient information
Prescription treatment information
This page names two prescription-only medicines that may be discussed as possible options after a medical consultation. Their inclusion does not mean that either medicine is suitable for you or will be prescribed.
Consultation first—medicine second
Mounjaro and Wegovy are prescription-only medicines. They are not automatically appropriate for everyone, and neither should be selected solely from information found online, a price comparison or a promise of a particular result. Eligibility, contraindications, other medicines, pregnancy, previous adverse effects and your individual priorities must be considered first.
Possible option after assessment
Mounjaro®
Active ingredient: tirzepatide.
The current patient leaflet describes Mounjaro as a once-weekly medicine used with a reduced-calorie diet and increased physical activity for weight loss and weight maintenance in eligible adults. It regulates appetite and may increase fullness, reduce hunger and reduce food cravings.
Common effects listed in the patient leaflet include nausea, diarrhoea, vomiting, abdominal pain and constipation. Loss of fluid through vomiting or diarrhoea can cause dehydration.
Important points to discuss include previous pancreatitis, severe digestive problems, diabetes medicines, planned surgery, pregnancy, contraception and breast-feeding. The current leaflet advises additional contraceptive precautions for four weeks after starting treatment and for four weeks after each dose increase when an oral contraceptive is used.
Possible option after assessment
Wegovy® injection
Active ingredient: semaglutide.
The current injection patient leaflet describes Wegovy as a once-weekly medicine used with diet and physical activity for weight loss and weight maintenance in eligible adults. It acts on appetite regulation and may increase fullness while reducing hunger and food cravings.
Common effects listed in the patient leaflet include nausea, vomiting, diarrhoea, constipation, stomach pain, headache and tiredness. Vomiting and diarrhoea can cause dehydration.
Important points to discuss include previous pancreatitis, diabetes and diabetic eye disease, delayed stomach emptying, planned surgery, anticoagulants, pregnancy and breast-feeding. The current leaflet advises stopping at least two months before a planned pregnancy.
Newly authorised in the UK
Wegovy® tablets (oral semaglutide)
On 11 June 2026, the MHRA authorised once-daily Wegovy tablets for weight management in eligible adults. This is a weight-management medicine in its own right and should not be confused with Rybelsus®, an oral semaglutide product used for type 2 diabetes.
Unlike the once-weekly injection, the tablet is taken every day on an empty stomach after fasting for at least eight hours, with no more than 120 mL of water. Food, drink and other oral medicines must wait for at least 30 minutes. It is not automatically interchangeable with the injection and requires an individual assessment and a separate dose-escalation plan.
Availability in Jersey: this is a newly authorised product. At the time of this page update (August 2026), reliable sources do not confirm that pharmacies in the Channel Islands can routinely obtain the complete Wegovy tablet range. Dr Greig will only offer this option once local supply, price and continuity can be confirmed with a registered pharmacy.
Medicine information and authorisations change. The linked electronic patient leaflets should be checked each time and take precedence over this summary.
Important safety information for both medicines
- Use only after assessment and exactly as prescribed. Never share prescription medicine or change your dose without clinical advice.
- Nausea, vomiting, diarrhoea and constipation are common. Maintain sensible hydration and contact Dr Greig if symptoms are troublesome or persistent.
- Severe, persistent abdominal pain—with or without nausea or vomiting—requires urgent medical assessment because it may indicate acute pancreatitis.
- Tell the surgical and anaesthetic team if you are due to have an operation or procedure requiring anaesthesia or sedation.
- Pregnancy, planned pregnancy, contraception and breast-feeding require medicine-specific advice.
- Only obtain prescription medicine from a legitimate registered pharmacy after a valid prescription.
Why this page does not say which medicine is “best”
There is no responsible online answer that applies to everyone. Suitability depends on your health, other medicines, previous experience, treatment response, adverse effects and the current authorised information. Dr Greig does not receive commission or referral payment from a dispensing pharmacy, and the decision is clinical—not a product sale.
Further official information: MHRA patient safety guidance and the medicine-specific electronic patient leaflets linked above.