Key takeaways:
Mounjaro (tirzepatide) doesn’t directly cause hair loss. But it can trigger telogen effluvium, a type of hair loss that can develop with rapid weight loss.
Telogen effluvium usually starts 3 months after rapid weight loss. It goes away on its own within a few weeks to a few months.
Limiting hair damage and using treatments to stimulate hair growth may help reduce hair loss from telogen effluvium.
Mounjaro (tirzepatide) is a weekly injectable medication that is FDA-approved to treat Type 2 diabetes. Another medication with the same active ingredient, called Zepbound, is FDA-approved for weight management.
Mounjaro lowers blood sugar by increasing the effects of two hormones — GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic peptide). These hormones make your body more sensitive to insulin and help slow down digestion. They also decrease hunger and food cravings, which can lead to weight loss.
Mounjaro is linked to several side effects, including some unexpected ones — like hair loss.
Mounjaro doesn’t directly cause hair loss. But most people who take Mounjaro lose weight. Rapid weight loss can lead to a temporary form of hair loss called telogen effluvium.
Hair follicles go through three phases:
Growth phase
Resting phase
Shedding phase
Each hair follicle goes through these cycles at slightly different times. This keeps all of your hair from falling out at once.
Most of the time, your hair is in the growth phase. But many things, including rapid weight loss, can shift hair follicles into the shedding phase. This is called telogen effluvium. When this happens, more hairs fall out at the same time, causing noticeable thinning and hair loss.
Telogen effluvium doesn’t happen right away. It can take up to 3 months after weight loss to see hair thinning and hair loss. Telogen effluvium will go away on its own. But it’ll take several months for your hair to shift back to its normal growth pattern. It can also take several more months for hair to grow back long enough to fill in thin areas.
In one recent study, nearly 1 in 4 people taking tirzepatide reported hair thinning or hair loss after losing weight. But it’s still unclear exactly how many people taking Mounjaro have this side effect because this side effect hasn’t been studied.
But here’s a piece of good news: some people have reported improved hair growth while taking Mounjaro. High blood sugar can cause hair thinning, so Mounjaro’s ability to lower blood sugar might help improve hair thickness.
If you take Mounjaro and are struggling with hair loss, here are a few things that may help.
Hair loss in women can happen for different reasons, depending on age. Learn about the various causes of hair loss in women and how they can be treated.
Telogen effluvium is a type of hair loss linked to stress. This reversible cause of hair thinning or loss can be triggered by any physical or emotional stressor
How does Mounjaro cause weight loss? Learn why this medication can lead to significant weight loss.
Weight management isn’t a quick process. Experts recommend only losing 5% to 10% of your body weight over 6 months. Losing weight faster than this can stress your body in many ways. Work with your healthcare team to make sure you don’t lose too much weight too fast.
Mounjaro lowers your appetite, which might make it harder to eat enough and get the right nutrition. It’s important to prioritize protein intake while taking Mounjaro. Aim for 25 g to 30 g of protein per meal. This will give your body the fuel it needs and lower stress on your body.
Not getting enough vitamins and minerals can add stress to your body and worsen hair loss. A shift in your eating patterns may make it harder to get all the vitamins and minerals you need. Your healthcare team can help you decide if you should take a daily multivitamin or other supplements while taking Mounjaro.
Consider working with a registered dietician while taking Mounjaro. Registered dieticians can help you develop a nutrition plan that meets your vitamin and protein goals while also supporting your weight management plan.
Some styling habits can damage your hair and even cause it to fall out. Try not to use hot styling tools, pull your hair back too tightly, or brush it when it’s wet. Avoid these things until your body recovers from telogen effluvium.
Weight loss can shift more hair follicles into their shedding phase, especially if you’re eating fewer calories. When more hair follicles shift into this phase, you may notice more hair thinning and hair loss.
Telogen effluvium will go away once your body adjusts to its new weight. When your hair follicles shift back to the growth phase, your hair will grow back. But this can take several months.
Rogaine (minoxidil) may help hair regrow after taking Mounjaro. But it’s not the first-choice treatment for telogen effluvium. Minoxidil works by improving blood flow to your scalp and allowing cells in your hair follicles to grow and divide. It doesn’t shift hair back into a growth phase faster. But it may nurture hair growth when your hair is ready to grow again.
Many people report hair loss after starting Mounjaro. This is likely due to rapid weight loss, not the medication itself. Luckily, hair loss as a result of weight loss is usually temporary. But if you’re still struggling with hair loss after your weight stabilizes, see your healthcare professional. There could be another reason for your hair loss.
American Academy of Dermatology Association. (n.d.). 10 hair care habits that can damage your hair.
Contreras, F., et al. (2024). Health benefits beyond the scale: The role of diet and nutrition during weight loss programmes. Nutrients.
DermNetNZ.org. (2019). Telogen effluvium.
Gordon, E. R., et al. (2024). Treatment of insulin resistance with tirzepatide leading to improvement of hair loss. JAAD Case Reports.
Ituarte, B. E., et al. (2024). Cross-sectional analysis of adverse dermatologic events reported to the FDA after use of GLP-1 agonists. Journal of Drugs in Dermatology.
Jastreboff, A. M., et al. (2022). Tirzepatide once weekly for the treatment of obesity. The New England Journal of Medicine.
Kang, D., et al. (2024). Telogen effluvium associated with weight loss: A single center retrospective study. Annals of Dermatology.
Koliaki, C., et al. (2018). Defining the optimal dietary approach for safe, effective and sustainable weight loss in overweight and obese adults. Healthcare.
Leidy, H. J., et al. (2015). The role of protein in weight loss and maintenance. The American Journal of Clinical Nutrition.
Lie, C., et al. (2018). Alopecia and the metabolic syndrome. Clinics in Dermatology.
Messenger, A. G., et al. (2004). Minoxidil: Mechanisms of action on hair growth. British Journal of Dermatology.
Office of Dietary Supplements. (n.d.). Nutrient recommendations and databases. National Institute of Health.
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