What should you know before starting Wegovy?

What does Wegovy do, and who may be eligible?

Semaglutide activates the glucagon-like peptide-1 (GLP-1) receptor, which is involved in appetite, insulin release and stomach emptying. It can change hunger and fullness, but it does not guarantee a particular change in weight or health. Nutrition, activity adapted to your ability, sleep and ongoing review remain part of care.

The adult UK weight-management licence uses body mass index (BMI), a measure relating weight to height, and weight-related conditions. Meeting licensing criteria does not automatically make treatment appropriate or provide NHS eligibility. NHS criteria differ by service and nation. Some injectable Wegovy use is licensed for adolescents under specific conditions; this requires specialist assessment, and the adult tablet licence should not be applied to children.

What should you tell the prescriber?

Share your full medicine list, including insulin, gliclazide, other weight-management products and supplements. Do not combine Wegovy with another semaglutide product or another GLP-1 medicine. Tell the clinician about pancreatitis, gallstones, kidney problems, severe delayed stomach emptying and diabetes-related eye disease. Diabetes treatment or eye monitoring may need review.

Older age alone is not a blanket UK contraindication, but frailty, muscle strength and nutrition matter. A past thyroid tumour or other endocrine condition should be discussed rather than applying US labelling as if it were the UK licence. A serious allergy to semaglutide or the product's ingredients prevents its use.

Tell any surgical or anaesthetic team that you take Wegovy: delayed stomach emptying can increase the risk of stomach contents entering the lungs during general anaesthesia or deep sedation. Follow their individual plan rather than stopping it yourself.

Are injections and tablets used the same way?

No. Wegovy has UK injectable and adult tablet formulations. The injectable treatment is weekly and the oral treatment is daily. Both contain semaglutide, but their doses and administration are not interchangeable. Your prescriber should identify the formulation and explain dose escalation, meaning a gradual increase to improve tolerability.

For weekly injections, learn how to use your actual UK device. Inject under the skin of the abdomen, thigh or upper arm as instructed, rotate sites, never share pens and dispose of needles safely. Do not follow a video for a different country's pen or estimate doses by counting clicks.

If a weekly injection is missed, the UK instructions allow it to be taken within five days; after more than five days, skip it and resume on the usual day. Never double a dose. If several doses are missed, ask about restarting rather than resuming a higher dose yourself. Tablets have different instructions: follow their leaflet for fasting, water, other medicines and missed doses. Do not switch formulations without a prescribed plan.

Which side effects can you discuss routinely?

Nausea, vomiting, diarrhoea, constipation and reflux can occur, particularly during escalation. Smaller meals and regular fluids may help, but persistent symptoms need review. Do not keep increasing the dose while struggling to eat or drink. Dehydration can affect kidney function, and very low intake can compromise nutrition and muscle strength.

Hypoglycaemia means low blood glucose. It is particularly relevant if you also use insulin or a sulfonylurea such as gliclazide. Agree on monitoring and treatment of low glucose before starting; do not adjust diabetes medicine on your own.

Which symptoms need urgent action?

Stop Wegovy and seek urgent medical help for severe persistent abdominal pain, especially if it spreads to your back, with or without nausea or vomiting. This can indicate pancreatitis, inflammation of the pancreas. If pancreatitis is confirmed, semaglutide should not be restarted.

Semaglutide is associated with non-arteritic anterior ischaemic optic neuropathy (NAION), a condition caused by reduced blood supply to the optic nerve. Sudden loss of vision, including partial loss, or rapidly worsening eyesight needs immediate eye casualty or A&E assessment. Semaglutide should be discontinued if NAION is confirmed. This warning is distinct from monitoring for diabetic retinopathy, damage to the eye's light-sensitive tissue caused by diabetes.

Repeated vomiting, inability to retain fluids, markedly reduced urine, jaundice or severe upper abdominal pain need prompt assessment. Call 999 for breathing difficulty, tongue or throat swelling, collapse or unconsciousness.

What if you are planning a pregnancy?

Do not use Wegovy during pregnancy or breastfeeding. Use effective contraception during treatment and stop semaglutide at least two months before trying to conceive. If pregnancy occurs, stop Wegovy and contact your prescriber promptly. Vomiting or severe diarrhoea can interfere with an oral contraceptive, so follow your pill's advice and seek pharmacy guidance. The additional four-week contraception rule for tirzepatide is not a general rule for Wegovy. This concerns semaglutide specifically; Foundayo carries its own precaution to use a non-oral method or add a barrier method for 30 days after starting and for 30 days after each dose increase.

What should ongoing review cover?

Review side effects, nutritional intake, strength, glucose where relevant, and whether treatment still fits your goals and health needs. Wegovy is not a licensed treatment for nicotine or alcohol dependence. Use only prescribed medicine from a registered pharmacy and keep your usual healthcare team informed. If stopping becomes appropriate, discuss support: appetite and weight can change afterwards.