Does Mounjaro cause hair loss?
While this medication is new and further research is needed to determine its impact on hair follicles, preliminary studies and patient reports suggest that Mounjaro can indeed cause hair loss. In fact, 2025 research found that tirzepatide puts you at greater risk of telogen effluvium (a type of temporary hair loss) compared with other weight loss medications [6].
A meta-analysis performed on 8 studies, with a total number of 8847 participants who received Mounjaro over 2 years revealed that approximately 5.7% of them experienced alopecia [2]. A different study found a 4% hair loss rate in patients treated with tirzepatide (the active substance in Mounjaro), compared to 0.7% in the placebo group [1].
These findings determined the company which produces Mounjaro to add hair loss to the list of potential adverse reactions, marked as a common event. The FDA is also currently investigating reports of hair loss and suicidal thoughts in diabetes and weight loss drugs such as Mounjaro, Ozempic and Wegovy [7].
However, more recent studies have shown a different picture. A 2025 research review encompassing 2905 patients found mixed results. Researchers reported that the study “yielded conflicting findings” — three of the tirzepatide studies showed that patients benefitted from improvement in hair growth, while two found patients were affected by hair loss [8]. Another 2025 study, which analysed more than 920,000 adverse events, found a “weak association” between hair loss and GLP-1 agonists including tirzepatide [9].
The mechanisms which make Mounjaro cause alopecia are still being researched. A new study agreed in October 2024 will examine the real-world impact of Mounjaro, and may shed more light on the relationship between Mounjaro and hair loss [10].
There are theories that the hair shedding could be caused by the impact of tirzepatide on your hormonal activity or your metabolism. Rapid weight loss is sometimes associated with nutritional deficiencies, which can cause hair loss, so rebalancing the diet to ensure you are getting an adequate amount of vitamins and minerals can help prevent hair loss.