From the Guidelines
The number needed to treat (NNT) for weight loss with Zepbound (tirzepatide) is approximately 1.5-2, meaning that for every 1.5-2 patients treated with Zepbound, one will achieve clinically significant weight loss compared to placebo.
Key Points
- Zepbound is highly effective for weight loss, with clinical trials showing that patients taking the maximum dose can lose an average of 20-22% of their body weight over 72 weeks 1.
- The medication works as a dual GIP/GLP-1 receptor agonist, which helps regulate appetite and food intake by slowing gastric emptying, increasing feelings of fullness, and affecting brain centers that control hunger.
- Treatment typically starts at a lower dose with gradual dose escalation every 4 weeks up to the maximum dose as tolerated.
- Common side effects include nausea, diarrhea, and constipation, which often improve over time 1.
- Patients should combine Zepbound with lifestyle modifications including calorie reduction and increased physical activity for optimal results.
- The low NNT reflects Zepbound's superior efficacy compared to other weight loss medications, though individual results may vary.
Comparison to Other Medications
- GLP-1 RA–based medications, such as semaglutide and liraglutide, also reduce lipids, BP, and glucose as well as weight, but Zepbound's dual GIP/GLP-1 receptor agonist mechanism may provide additional benefits 1.
- Phentermine/topiramate and naltrexone/bupropion are associated with increased risk of adverse effects, such as increased heart rate, mood and sleep disorders, and impaired cognitive function 1.
- Orlistat has modest effects on weight, but is associated with significant gastrointestinal adverse effects 1.
From the Research
Number Needed to Treat for Weight Loss with Zepbound
There are no research papers to assist in answering this question as the provided studies do not mention Zepbound.
Available Information on Other Weight Loss Medications
- The following medications have been approved by the FDA for chronic weight management: orlistat, phentermine/topiramate, naltrexone/bupropion, and liraglutide 2.
- A systematic review and meta-analysis found that phentermine/topiramate, liraglutide, naltrexone/bupropion, lorcaserin, and orlistat were associated with significant weight loss compared to placebo 3.
- Phentermine/topiramate therapy resulted in an average weight loss of 7.73 kg compared to placebo, with the weight loss related to the dose of phentermine/topiramate 4.
- A systematic review compared the effectiveness of semaglutide, liraglutide, orlistat, and phentermine for weight loss in obese individuals, highlighting the importance of integrating pharmacotherapy with lifestyle interventions 5.
- Longer-term use of phentermine was associated with greater weight loss without increased risk of incident cardiovascular disease or death 6.