Overview

• A meta-analysis of 11 randomized trials with 1,574 treatment and 893 control participants found weight regain starts about eight weeks after stopping anti-obesity medications and continues for roughly 20 weeks before stabilizing.
• Patients who switched from a 36-week tirzepatide regimen to placebo recaptured nearly half of their lost weight within weeks of discontinuation.
• At 52 weeks after drug withdrawal, participants remained below their initial weight but had recouped a substantial portion of their treatment-period losses.
• Six FDA-approved drugs—including GLP-1 receptor agonists, orlistat, phentermine-topiramate and naltrexone-bupropion—exhibited similar rebound trajectories regardless of mechanism.
• NHS figures show 2.7 million weight-loss injection prescriptions in England last year, underscoring concerns about insufficient diet and lifestyle support alongside widespread drug use.