The full menu of approved options
From injectable GLP-1 and dual agonists to oral combinations and a lipase inhibitor, the FDA-approved arsenal now spans a wide efficacy range — roughly 2.4% to 20.9% placebo-adjusted weight loss. The right choice depends on your biology, your tolerance, and your goals. This table lays out the entire landscape.
| Generic Name | Trade Name(s) | Receptor Targets & Class | FDA Status | Placebo-Adjusted Weight Loss Efficacy | Primary Biological Action | Source |
|---|---|---|---|---|---|---|
| Tirzepatide | Zepbound (weight loss), Mounjaro (diabetes) | Dual GLP-1 and GIP receptor agonist | Chronic weight management (FDA-approved 2023) | 17.8%–20.9% (at 15 mg dose) | Slowing gastric emptying, increasing satiety, and improving glycemic control via dual-action central signaling | 2, Background Knowledge, Inferred, Wikipedia Anti-Obesity Medications |
| Semaglutide | Wegovy (weight loss), Ozempic (diabetes) | Selective GLP-1 receptor agonist | Chronic weight management (FDA-approved 2021) | 12.0%–12.4% | Slowing gastric emptying and central appetite suppression via the hypothalamus to reduce cravings | 3, 2, Background Knowledge, Inferred, Wikipedia Anti-Obesity Medications |
| Phentermine/topiramate | Qsymia | Substituted amphetamine (Sympathomimetic amine) / GABA modulator & carbonic anhydrase inhibitor | Chronic weight management (also indicated for short-term) | 8.8%–10.2% | Appetite suppression via norepinephrine release and increased satiety via neurotransmitter modification | Background Knowledge, Inferred, Wikipedia Anti-Obesity Medications |
| Liraglutide | Saxenda (weight loss), Victoza (diabetes) | Selective GLP-1 receptor agonist | Chronic weight management | 4.0%–5.4% | Regulation of appetite and calorie intake by slowing gastric emptying and increasing feelings of fullness | Background Knowledge, Inferred, Wikipedia Anti-Obesity Medications |
| Naltrexone/bupropion | Contrave | Opioid antagonist / Norepinephrine-dopamine reuptake inhibitor (NDRI) | Chronic weight management | 4.0%–5.0% | Targets the reward system (mesolimbic) and hypothalamus to reduce food cravings and appetite | Background Knowledge, Inferred, Wikipedia Anti-Obesity Medications |
| Phentermine | Adipex-P, Lomaira | Substituted amphetamine (Sympathomimetic amine; TAAR1 agonist) | Short-term use (up to 12 weeks) | 3.0%–4.0% (or ~5 kg / 11 lb) | Stimulation of norepinephrine release to suppress appetite | Background Knowledge, Inferred, Wikipedia Anti-Obesity Medications |
| Orlistat | Xenical (Prescription), Alli (OTC) | Gastric and pancreatic lipase inhibitor (Non-receptor) | Chronic weight management | 2.4%–4.0% (or ~3 kg / 6.6 lb) | Inhibition of gastrointestinal lipases to prevent the absorption of dietary fat in the intestines | 3, Background Knowledge, Inferred, Wikipedia Anti-Obesity Medications |
| Sibutramine | Meridia | Not in source | Withdrawn | Not in source | Appetite suppression |
Reading the table
Efficacy climbs with receptor coverage: selective GLP-1 (Wegovy) hits ~12%, the dual GLP-1/GIP agonist tirzepatide (Zepbound) reaches ~18–21% at the top dose, and oral/combination options (Qsymia, Contrave) occupy the 4–10% band with a different side-effect profile. Lower efficacy is not worse — it is often the right trade for someone who tolerates oral meds or needs short-term support.
The short version
- The FDA-approved arsenal now spans roughly 2.4% to 20.9% placebo-adjusted weight loss across seven distinct prescription drug options.
- Tirzepatide (Zepbound), a dual GLP-1 and GIP receptor agonist approved in 2023, leads with 17.8%-20.9% loss at the 15 mg dose.
- Semaglutide (Wegovy), a selective GLP-1 receptor agonist approved in 2021, produces 12.0%-12.4% loss by slowing gastric emptying and suppressing appetite centrally.
- Phentermine/topiramate (Qsymia) produces 8.8%-10.2% loss by suppressing appetite and increasing satiety, while liraglutide (Saxenda) produces 4.0%-5.4% loss as a daily injection.
- Naltrexone/bupropion (Contrave) produces 4.0%-5.0% loss by targeting the mesolimbic reward system, while phentermine alone is approved only up to 12 weeks.
- Orlistat (Xenical/Alli) is a non-receptor gastric and pancreatic lipase inhibitor producing 2.4%-4.0% loss by blocking dietary fat absorption.
Choose with a provider, not a comment section
Every option in this table is a prescription for a reason. Get matched with a local weight-loss provider who can match your profile to the right class — free, no obligation.
