Nonscarring hair loss associated with GLP-1RA use

Photo by Welshsk via Wikimedia Commons

The use of glucagon-like peptide-1 receptor agonists (GLP-1RAs), widely used to manage type 2 diabetes mellitus (T2DM) and obesity, appears to increase the risk of nonscarring hair loss (NSHL).

These findings were published online ahead of print in the Journal of the American Academy of Dermatology.

In the paper, the authors note that emerging reports suggest potential dermatologic adverse effects associated with GLP-1RA use, particularly NSHL.

To better understand the dermatologic side-effect profile and safety of this class of medications, researchers evaluated data from the TriNetX US Collaborative Network, a platform that aggregates de-identified electronic health record data from 67 U.S. healthcare organizations.

In the study, investigators assessed the incidence and risk of NSHL in adults (18–89 years) and adolescents (12–17 years) treated with GLP-1Ras compared with matched controls from 2014–2024. They included patients with two or more GLP-1RA prescriptions, while controls had ≥2 general medical encounters and no GLP-1RA exposure. The authors excluded patients with confounding dermatologic, endocrine, nutritional, or systemic conditions.

Between 2014 and 2024, the incidence of NSHL, telogen effluvium (TE), androgenic alopecia (AGA), and alopecia areata (AA) increased in both GLP-1RA users and controls. Beginning around 2019, incidence curves for overall NSHL began to diverge, with GLP-1RA users showing consistently higher rates by 2023–2024. For TE and AGA, rates remained similar until 2021–2022, after which they rose more sharply among GLP-1RA users. Ten or fewer pediatric GLP-1RA users experienced each hair loss outcome of interest, precluding meaningful comparisons. At six months, GLP-1RAs were linked to a higher risk of AGA (adjusted odds ratio (aOR) 1.62) and NSHL (aOR 1.26) (both p<0.001) and increased TE risk (p=0.18). At 12 months, risks increased for TE (aOR 1.76), AGA (aOR 1.64), and NSHL (aOR 1.40), all p<0.001.

The authors suggest that likely mechanisms for the observed associations between GLP-1RA use and increased risk of NSHL include rapid weight loss, insulin/IGF-1 signalling, androgen changes, and direct follicular effects. They say their findings align with prior studies linking alopecia to the GLP-1RAs semaglutide and tirzepatide.

AA was consistently higher in controls, suggesting GLP-1RAs do not significantly affect autoimmune hair loss.

The researchers note the small sample size in the pediatric subset limited analysis, highlighting barriers to access to GLP-1RAs in children.

“Awareness of alopecia risk in patients on GLP-1RAs is critical for early detection, anticipatory guidance, and multidisciplinary care,” the authors write in their conclusion. “Future research should examine underlying mechanisms, prospective monitoring, and pediatric outcomes to guide safe and informed GLP-1RA use.”