Research
Mixed
Anti-obesity drugs (phentermine/topiramate, liraglutide, naltrexone/bupropion, lorcaserin, orlistat) produce clinically significant weight loss (2.9% to 6.8% placebo-subtracted) over 12+ months, but require careful risk-benefit assessment due to adverse effects and high cost.
If lifestyle changes aren't enough, anti-obesity drugs can help you lose 3-7% more weight than placebo over a year. However, these drugs have side effects and costs. You must discuss your specific health history with a doctor to choose the right option, as some drugs have been withdrawn due to safety concerns like cancer risk.
GoodQualifiesHIGH confidence
Data from most recent meta-analyses showed that the overall placebo-subtracted weight reduction (%) with the use of anti-obesity drugs for at least 12 months ranges from 2.9% to 6.8%; phentermine/topiramate (-6.8%) liraglutide (-5.4%), naltrexone/bupropion (-4.0%), lorcaserin (-3.1%), and orlistat (-2.9%). However, they have a high cost and may cause adverse outcomes depending on the individual.
Why this rating
Based on meta-analyses of RCTs, though the paper is a review.
Source
Anti-Obesity Drugs: Long-Term Efficacy and Safety: An Updated Review
Young Jin Tak et al. · The World Journal of Men s Health · 2020
DOI 10.5534/wjmh.200010
narrative_reviewCited 174×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Lorcaserin was withdrawn from the US market in 2020 due to an increased risk of cancer observed in clinical trials, despite showing modest weight loss efficacy.Strong
- Phentermine/topiramate ER produces the highest placebo-subtracted weight loss (6.8%) among approved anti-obesity drugs, with significant improvements in cardiovascular risk factors.Good
- Liraglutide (3.0 mg) produces significant weight loss (-5.4% placebo-subtracted) and improves cardiovascular risk factors, but has a high discontinuation rate due to gastrointestinal side effects.Good
Related findings · Mixed
- Bariatric surgery (VSG and RYGB) is the most effective and sustainable treatment for obesity, producing marked and sustained weight loss that non-surgical interventions cannot match.Strong
- Severely protein-deficient diets (2–3% energy) induce lean body mass loss and metabolic imbalance, whereas adequate protein intake (0.66 g/kg/d minimum) is a prerequisite for maintaining muscle, bone, and physiological function.Strong
- For patients with Class III obesity (BMI >39.9 kg/m2), metabolic bariatric surgery (MBS) is significantly more effective than any currently approved medication, with BilioPancreatic Diversion (BPD) showing the highest estimated weight loss.Strong
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