Wegovy and Mounjaro represent a new class of weight-loss medications that work by mimicking GLP-1, a hormone that regulates appetite and blood sugar. Both drugs inject a synthetic version of this hormone, signaling the brain to feel fuller faster and reducing cravings for food.
Wegovy, made by Novo Nordisk, targets weight loss directly. Mounjaro, produced by Eli Lilly, was originally designed for type 2 diabetes but shows comparable weight-reduction effects. The mechanism operates through the GLP-1 receptor pathway, slowing gastric emptying so food stays in the stomach longer, creating prolonged satiety.
In clinical trials, patients using these drugs lost significantly more weight than those on placebo alone. Weekly injections produce effects that persist throughout the week, making adherence simpler than daily pill regimens. Results typically appear within weeks, though maximum benefit develops over several months.
The NHS now covers these medications for certain eligible patients, typically those with a BMI above 30 or 35 with weight-related conditions. Private prescriptions remain available for others willing to pay out-of-pocket costs, which run hundreds of pounds monthly.
Side effects include nausea, vomiting, and gastrointestinal distress, particularly early in treatment. Some users experience rapid weight regain after stopping the medication, suggesting these drugs work best as sustained treatments rather than short-term interventions.
The surge in demand has created supply shortages globally. Novo Nordisk and Eli Lilly continue expanding manufacturing to meet healthcare system needs and private demand. Both companies face competition as other pharmaceutical firms develop competing GLP-1 medications, signaling this category will reshape obesity treatment for years ahead.