New research suggests that Mounjaro, a popular weight loss and diabetes medication, may be more likely to cause hair loss in women than similar drugs like Wegovy and Ozempic. An Australian study found that approximately one in 18 women using Mounjaro experienced new-onset alopecia within the first year, compared to one in 30 women using semaglutide, the active ingredient in Wegovy and Ozempic.
Earlier this month, U.S. researchers reported that these popular injections are about 70 percent more likely to cause hair loss than other diabetes medications. The latest study, conducted by the health research firm nference, analyzed data from 11,046 patients taking Mounjaro and an equal number taking semaglutide. Overall, about 4 percent of Mounjaro users reported hair loss, compared to just under 3 percent of users of other GLP-1 agonists and diabetes medications. However, when the analysis focused solely on women, the incidence of hair loss was around 6 percent for Mounjaro users versus 3 percent for those on other treatments.
The risk of hair loss associated with Mounjaro appeared to be higher regardless of the amount of weight lost or the dosage received. Researchers noted that women may be more inclined to seek medical attention for hair loss due to social stigma, which could influence the findings. Venky Soundararajan, the study's lead author, suggested that the results support more personalized patient counseling and monitoring rather than a general warning about weight loss inevitably causing hair loss.
Experts theorize that the hair loss may be linked to the rapid weight loss and associated nutritional deficiencies experienced by patients, rather than the drugs themselves. This type of hair loss is generally non-scarring, meaning hair follicles are not destroyed and hair can potentially regrow. However, underlying hormonal or metabolic factors may also play a role, as alopecia was found to be more common in patients with pre-existing thyroid disease or other hormonal conditions. The mechanism of GLP-1 agonists, which slow stomach emptying and reduce hunger, could also potentially affect the absorption of certain medications, such as thyroid hormone therapies, which might influence hair growth.
The U.S. Food and Drug Administration (FDA) is currently evaluating the effect of Wegovy, Ozempic, and Mounjaro on hair loss. In the UK, regulatory agencies have received hundreds of reports of hair loss associated with these drugs. While the absolute risk is considered low by some experts, the findings emphasize the importance of informed discussions between healthcare providers and patients, particularly for women or individuals with a history of hair loss, autoimmune conditions, or nutrient deficiencies.