How does Wegovy’s impact on appetite compare to that of other weight loss medications?

Wegovy works directly on appetite signals in the brain, helping people feel full sooner and think less about food. Other medicines act differently — Orlistat blocks fat absorption without reducing hunger, while Mysimba works on brain reward pathways but has less impact on satiety than semaglutide.

How Wegovy influences appetite

Wegovy contains semaglutide, a GLP-1 receptor agonist. This medicine mimics a natural hormone that plays a role in hunger and satiety. It slows the emptying of the stomach, stimulates insulin release, and crucially, acts on areas of the brain that regulate appetite. In practice, people taking Wegovy often report fewer food cravings, feeling satisfied with smaller portions, and thinking less about eating between meals. Clinical trials back this up, with participants in the STEP programme losing about 15% of their body weight over 68 weeks, largely due to reduced calorie intake.

Orlistat: blocking fat, not hunger

Orlistat works in a very different way. It blocks the absorption of dietary fat in the gut, which reduces calorie intake but does not directly change appetite. As a result, people taking Orlistat still experience normal hunger levels. Its effectiveness depends heavily on sticking to a low-fat diet, since eating too much fat while on Orlistat can cause unpleasant side effects such as oily stools. This makes it less about appetite control and more about dietary management.

Mysimba: cravings and reward pathways

Mysimba (naltrexone/bupropion) targets the brain’s reward system, helping reduce cravings and emotional eating. It can be helpful for people who struggle with strong urges to snack or eat in response to stress. However, its effect on satiety is weaker than Wegovy’s. In clinical trials, weight loss with Mysimba averaged 6–9% of body weight over a year, compared with the much larger reductions seen with semaglutide.

Saxenda and other GLP-1 medicines

Saxenda (liraglutide) is another GLP-1 receptor agonist, taken daily rather than weekly. Like Wegovy, it reduces appetite and helps people feel full sooner, though to a lesser degree. In the SCALE trials, Saxenda led to around 6–8% weight loss over a year. By comparison, Wegovy’s weekly dosing and higher semaglutide dose produced more powerful appetite suppression and greater weight reduction in head-to-head studies.

Why appetite control matters

Appetite is a key driver of long-term weight management. Medicines that reduce hunger tend to produce better sustained results, because they make it easier for people to stick to lower-calorie diets without constant feelings of deprivation. This is where Wegovy has a clear advantage over older options like Orlistat and over non-GLP-1 medicines like Mysimba. The combination of appetite suppression and metabolic benefits sets it apart.

NHS perspective

NICE guidance highlights that Wegovy should always be used alongside a reduced-calorie diet and physical activity, but its ability to reduce appetite makes those changes more realistic for many people. Orlistat and Mysimba remain available, but their uptake has been limited compared with GLP-1 medicines because they do not influence hunger as strongly.

The full perspective

In terms of appetite control, Wegovy is more effective than most other licensed weight-loss drugs. By acting directly on the brain’s satiety signals, it reduces cravings and supports lasting changes in eating behaviour. Orlistat works only on fat absorption, while Mysimba helps with cravings but produces smaller effects on satiety. Saxenda also reduces appetite but is less effective than Wegovy. This explains why Wegovy is now the preferred option in NHS weight-management services.