Nonscarring Alopecia in Adults Treated With GLP ‐1s: A Propensity Score Matched TriNetX Cohort Study

OBJECTIVE(S): GLP-1 receptor agonists (GLP-1s) are widely prescribed for type 2 diabetes (T2DM) and obesity, but associated hair loss outcomes remain poorly characterized. We evaluated whether GLP-1s were associated with different subtypes of hair loss in adults with T2DM or obesity. METHODS: This retrospective TriNetX cohort study included adults with established care from 2018 to 2025. GLP-1 users were grouped by indication and propensity score matched to nonusers by demographics, comorbidities, and hair loss-associated medications. Outcomes were new diagnoses of nonscarring alopecia, telogen effluvium, and alopecia areata as a negative control. Hair loss outcomes were assessed at 1, 3, and 5 years after semaglutide initiation and 1, 1.5, and 2 years after tirzepatide initiation. Secondary analyses compared semaglutide and tirzepatide with other GLP-1s and evaluated differences in follow-up BMI between patients with and without hair loss outcomes. RESULTS: Semaglutide and tirzepatide were associated with higher odds of other nonscarring alopecia across T2DM and BMI cohorts. Telogen effluvium odds were elevated with semaglutide use at 3 and 5 years and with tirzepatide at all follow-up periods. Compared with other GLP-1s, both medications showed higher odds of other nonscarring alopecia; tirzepatide also showed higher odds of telogen effluvium. Follow-up BMI was lower in GLP-1 users with hair loss than without hair loss. Alopecia areata was not associated with GLP-1 use. CONCLUSION: Semaglutide and tirzepatide were associated with higher odds of nonscarring hair loss, particularly telogen effluvium. This association and follow-up BMI findings suggest that weight loss-associated physiologic stress may contribute to hair loss during GLP-1 therapy.