Popular Weight-Loss Medications: A Comprehensive Overview
Popular Weight-Loss Medications: An Overview
1. Tirzepatide (Zepbound / Mounjaro): Tirzepatide targets both GLP-1 and GIP receptors, regulating blood sugar, boosting insulin, and slowing gastric emptying. It delivers the strongest results among this drug class — average weight loss of up to 22.5% of body weight, with 91% of participants losing at least 5%. Beyond weight loss, it improves blood pressure and glycemic control and is FDA-approved for obstructive sleep apnea in obese adults. Common side effects include nausea, vomiting, and diarrhea, which are usually temporary; about 4–8% of patients discontinue due to GI issues.
2. Semaglutide (Wegovy / Ozempic / Rybelsus): Semaglutide activates the GLP-1 receptor to stimulate insulin, suppress glucagon, and promote fullness. Injectable Wegovy achieves an average weight loss of up to 14.9%; the pill form reaches up to 16.6%. It also carries an FDA indication to reduce cardiovascular risk in overweight patients with known heart disease, and is approved for adolescents aged 12 and older. Side effects are similar to tirzepatide, with rare but serious risks including pancreatitis and gallbladder disorders.
3. Phentermine/Topiramate (Qsymia): This oral combination works through two pathways: phentermine suppresses appetite via norepinephrine release, while topiramate increases thermogenesis and reduces appetite. Average weight loss is around 9.1% — the highest among older oral agents. It modestly lowers blood pressure but carries notable risks: potential birth defects (requiring effective contraception), dry mouth, tingling, and cognitive side effects like brain fog.
Key Takeaways: Stopping these medications typically leads to weight regain due to metabolic adaptation — not personal failure. All should be used alongside diet and exercise changes, and the right choice depends on individual health history and tolerability. Consult a healthcare provider to determine the best option.