The risk of hair loss, primarily reversible non-scarring alopecia, increases with treatment with drugs of the GLP-1 receptor agonist (GLP-1) category, which are actively used for weight loss, scientists from the University of Pennsylvania confirmed. In the study, published in The BMJ, they compared the drug semaglutide, used under the brand name Ozempic, and its analogues with other categories of drugs originally developed to treat diabetes.
GLP-1 drugs act by mimicking the hormone incretin, which helps reduce appetite and blood sugar levels in people suffering from type 2 diabetes and excess weight. The other two drug categories in the study were SGLT-2 and DPP-4 inhibitors. The former lowers blood sugar by causing the kidneys to excrete glucose in the urine, while the latter helps regulate glucose levels by prolonging the action of hormones that increase insulin production. These categories of substances have not been approved as weight loss drugs in the United States.
Scientists studied thousands of electronic medical records for the period from January 2019 to September 2024 and concluded that patients on semaglutide and analogues went bald 37% more often than those who took SGLT-2 inhibitors. Compared to DPP-4, GLP-1 was associated with hair loss 68% more often.
“Use of GLP-1 receptor agonists was associated with a higher incidence of clinically reported hair loss, especially without scarring alopecia, in patients with type 2 diabetes compared with SGLT-2 and DPP-4 inhibitors,” the study said.
The authors noted that overall, the absolute risk of hair loss with GLP-1 receptor agonists is low, but clinicians should consider the observed differences between drug categories when prescribing treatment for diabetics.
Doctors took into account various risk factors – age, gender, ethnicity and existing diseases. The absolute risk of hair loss over the course of a year was approximately 7 cases per 1,000 people when taking GLP-1, 5 when using SGLT-2 and 4 when using DPP-4.
Researchers believe that the association of GLP-1 therapy with alopecia may be due to rapid weight loss, iron and zinc deficiency, and disruption of the hair growth cycle.
The scientists noted the need for further research to clarify the underlying mechanisms of hair loss, assess the clinical severity and reversibility of this process, and identify patients who may be at higher risk of alopecia.
The problem of excess weight affects millions of Americans. As RTVI reported, in the United States, doctors announced the appearance of cardiovascular-renal-metabolic syndrome in 9 out of 10 residents of the country due to excess body weight. There has also been a reported increase in illegal prescriptions for drugs like Ozempic this year.
