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What to Expect

Will I lose my hair on semaglutide or tirzepatide?

Updated 2026-05-02

Some people do. It's not the drug attacking your hair - it's your body reacting to rapid weight loss. Doctors call this telogen effluvium. Hair shedding typically starts 2 to 3 months after major weight loss and lasts 3 to 6 months. It's almost always temporary. Hair regrows in about 95% of acute cases. In the trials: Wegovy 3% vs 1% placebo; Zepbound 5% vs 1% placebo, with women hit harder (7.1% vs 0.5% in men).

IfIf you notice extra hair in your brush around month 3 to 4
Thenthen it's likely telogen effluvium - temporary, and it grows back
IfIf shedding is distressing
Thenthen talk to a dermatologist - minoxidil and checking iron/protein levels can help
IfIf shedding continues past 6 months without improving
Thenthen ask your doctor to check thyroid and iron levels
Key facts
  • Telogen effluvium mechanism: rapid weight loss is a physiological stressor that pushes up to 70% of hair follicles from anagen (growth) to telogen (resting/shedding) at the same time
  • Onset: typically 2 to 3 months after a significant weight loss event
  • Duration: shedding period 3 to 6 months; hair regrows in about 95% of acute cases
  • Not unique to GLP-1s - the same effect occurs after bariatric surgery
  • Zepbound label data: 5% (5 mg), 4% (10 mg), 5% (15 mg) vs 1% placebo; female 7.1% vs male 0.5%; no patients discontinued due to hair loss
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