GLP-1 and metabolic medicine

Wegovy

Also called: semaglutide 2.4 mg, Wegovy pen, weight-loss semaglutide

Wegovy is a brand name for semaglutide injections licensed for weight loss in adults with obesity or overweight with weight-related health conditions. It is the same drug as Ozempic but at a higher weekly dose of up to 2.4 mg. It works by mimicking the gut hormone GLP-1, which lowers appetite and slows stomach emptying.

What Wegovy is and is not

Wegovy is semaglutide, the same molecule sold as Ozempic for type 2 diabetes. It is licensed at higher doses (up to 2.4 mg weekly) specifically for weight management. NICE recommends it on the NHS for adults with a BMI of at least 35 plus a weight-related condition, accessed through specialist weight-management services. Most UK users currently pay privately.

How it works

Semaglutide activates GLP-1 receptors in the brain and gut. Three things happen at once: stomach emptying slows so food sits longer and you feel full sooner, the brain registers fullness at a lower food volume, and craving signals between meals quiet down. Average weight loss in the STEP trials was about 15 percent of body weight at 68 weeks, against around 2.4 percent on placebo.

The dose ladder

  1. Week 1 to 4: 0.25 mg weekly. Starter dose, mostly for tolerance.
  2. Week 5 to 8: 0.5 mg weekly. Mild appetite suppression begins.
  3. Week 9 to 12: 1.0 mg weekly. Most people notice meaningful changes here.
  4. Week 13 to 16: 1.7 mg weekly. Bigger appetite drop, side effects often peak briefly.
  5. Week 17 onwards: 2.4 mg weekly. The full maintenance dose.

Side effects to expect

  • Nausea: very common in the first 8 weeks and after each dose increase. Usually settles within a fortnight.
  • Constipation: common (around 17 percent of users on the 2.4 mg dose in STEP 1) because gut transit is genuinely slowed. Daily fluid, fibre and movement matter more than usual.
  • Reflux and burping: stomach contents linger, pressure builds.
  • Tiredness and headache: often related to the lower calorie intake itself, not the drug directly.
  • Hair shedding: reported by a meaningful minority. Linked to rapid weight loss and lower protein intake, usually reversible.
  • Rare but serious: pancreatitis, gallstones, severe gastroparesis. Persistent severe abdominal pain warrants stopping the drug.

What happens after you stop

Two thirds of weight lost is regained within a year of stopping in trial extensions. Appetite signalling returns to baseline within weeks. Most weight-management specialists treat Wegovy as a long-term medication rather than a course of treatment. The economic question this raises is real and unresolved.

Common questions

Is Wegovy on the NHS?
Available in principle but rationed in practice. NICE TA875 recommends Wegovy for adults with BMI 35 or over plus a weight-related condition, accessed through specialist Tier 3 weight-management services. The number of those services is limited, so most UK users currently pay privately.
Wegovy vs Ozempic, which is better?
They are the same drug. Wegovy is licensed and dosed for weight loss, Ozempic for diabetes. If your reason is diabetes with obesity, both could be prescribed depending on local pathways. If your reason is weight loss alone, Wegovy is the licensed option.
Does Wegovy work for everyone?
About 86 percent of users in STEP 1 lost at least 5 percent of body weight at 68 weeks, around 69 percent lost at least 10 percent, and roughly half lost at least 15 percent. A minority are non-responders for reasons that are not yet well understood. Tirzepatide (Mounjaro) is sometimes tried for non-responders.
Can I drink alcohol on Wegovy?
Modest amounts are usually fine. Many users report alcohol stops feeling pleasant or causes more nausea than usual, which is being studied. Heavy drinking remains a bad idea on any GLP-1 drug because of pancreatitis and dehydration risk.

Sources