Hair Loss on Ozempic, Wegovy, Zepbound or Mounjaro: Why It Happens and What Helps

Yes, semaglutide (Ozempic, Wegovy) and tirzepatide (Zepbound, Mounjaro) can make you shed more hair than usual. The US labels for Wegovy and Zepbound list hair loss among their common side effects and link it to weight loss^[1,2]. The most likely explanation is telogen effluvium: diffuse, temporary shedding that shows up weeks or months after losing a lot of weight^[7]. Here I go through what the labels say, why it happens, how long it usually lasts, what eating well can and can’t do, and when to see a doctor.

What the FDA labels say

I went through the adverse reactions in the US prescribing information for Wegovy, Zepbound (tirzepatide for weight), Ozempic and Mounjaro (tirzepatide for type 2 diabetes).

US labels checked on September 23, 2026 (Wegovy in its June 18, 2026 DailyMed version, Zepbound and Mounjaro revised 8/2026, Ozempic in its June 2026 version). The Wegovy label also reports hair loss in 4% of adolescents 12 and older on 2.4 mg, vs. none on placebo^[1].

The US label is silent on how severe the shedding was, whether it went away and how it relates to the amount of weight lost. The EU prescribing information for Wegovy fills in those gaps, so I use it only for them. With the injection, hair loss was mostly mild, most people recovered while staying on treatment, and it was more frequent in people who lost 20% of their weight or more. With the tablets, which the EU does break out, hair loss was reported in 6.4% vs. 2.0% on placebo; all cases were mild or moderate, and half had resolved by the end of the trial^[5]. The EU information for Ozempic doesn’t list hair loss at all^[6].

The evidence outside the labels points the same way. A 2026 systematic review included 24 studies: semaglutide and tirzepatide had the highest hair-loss rates in the drug class. With semaglutide, the effect looked dose-dependent, and doses under 2 mg a week, the ones used for diabetes, were rarely implicated. The authors note that the studies are very different from each other and the results inconsistent; some find no higher risk^[7].

Why hair falls out: telogen effluvium

Each hair goes through a cycle. According to a 2020 dermatology review, about 90% of scalp hair is in the growth phase (anagen), which lasts 2 to 5 years. About 10% is in the resting phase (telogen), which lasts 3 to 5 months and ends with that hair falling out^[8].

A strong physical stress can push many follicles into the resting phase at once. Weeks or months later, those hairs fall out together. That’s telogen effluvium: shedding spread over the whole scalp, with no bald patches or scarring^[8]. Known triggers include high fever, childbirth and surgery, and, according to MedlinePlus, crash diets, especially those without enough protein^[8,13]. The American Academy of Dermatology (AAD) lists losing 20 pounds or more among the usual triggers^[16].

Losing a lot of weight is one of them, with or without medication:

• In a 2024 Korean dermatology study of 140 people with telogen effluvium after weight loss, the average loss was 15.2% of body weight, at about 3.5 kg (7.7 lb) a month. It’s a retrospective study, based on weights the patients recalled^[9].
• After bariatric surgery, a 2025 meta-analysis of 41 studies with 7,044 patients estimates that 47% had hair loss^[10].

For GLP-1 medications, the 2026 review considers the shedding likely to have several causes, mainly rapid weight loss, eating fewer calories and hormonal shifts. So far, no study in humans suggests these drugs act directly on the hair follicle. The review also points out that telogen effluvium can unmask hereditary pattern hair loss (androgenetic alopecia) that was already there but not yet visible^[7].

When it starts and how long it lasts

On a GLP-1 there isn’t a single stressful day, like an operation: your weight goes down over months. That’s why the shedding can start without any obvious link to something specific. What the data say is that the acute form is usually temporary. In the Korean study everyone improved^[9], and the EU information for Wegovy says most people recovered while staying on treatment^[5].

The AAD adds a useful caveat: if the stress that set it off continues, the shedding can go on longer^[16]. According to the 2020 review, the longer it lasts, the more likely there’s more than one trigger, such as a nutrient deficiency or a thyroid problem^[8].

Who is more likely to shed

• People who lose more weight. The EU information for Wegovy reports more hair loss in people who lost 20% of their weight or more^[5]; the US label doesn’t break this out. How much you lose depends on the drug, the dose and the person; I go through the trial numbers in how much weight people lose on GLP-1 medications.
• Women. On Zepbound, 7.1% of women vs. 0.5% of men^[2]. In the Korean study, women developed it while losing weight more slowly than men: 3.1 kg (6.9 lb) vs. 5.0 kg (11 lb) a month^[9].
• Older people. In the same study, the older the person, the smaller the weight loss at which the shedding appeared^[9].

The 2026 review notes that women are also more likely to notice hair loss and see a doctor about it, which may inflate the numbers somewhat. Even so, it considers that this alone doesn’t explain the difference^[7].

What eating well can do, and what it can’t

A caveat first: no trial has tested whether any particular diet prevents hair loss on a GLP-1. What follows makes sense for other reasons, and it doesn’t replace your doctor’s assessment.

Eat enough, with enough protein. The 2025 joint advisory from four US obesity and nutrition societies notes that people on these drugs eat 16% to 39% fewer calories. Below 1,200 kcal a day for women or 1,800 for men, the risk of falling short on nutrients goes up. On protein, the advisory notes that 1.2 to 1.6 g per kilogram a day (0.54 to 0.73 g per pound) has been proposed during weight loss, or a fixed target of 80 to 120 g a day^[11]. You can estimate your own range with the protein calculator, and I go deeper in protein and muscle on GLP-1 medications. The big picture is in what to eat on GLP-1 medications.

With a small appetite, the advisory suggests eating the protein-rich foods first in a meal, and choosing foods that pack a lot of protein into a small volume, such as fish, eggs, Greek yogurt or cottage cheese^[11]. For tough mornings, there are 12 high-protein breakfasts for days when you have no appetite.

Deficiencies your doctor can check for. Among the nutrients to watch on GLP-1 medications, the advisory lists iron, zinc and vitamin B12, along with others. It also names excessive hair loss among the signs of a deficiency, alongside tiredness beyond what you’d expect and flaky skin^[11]. If you notice them, your doctor can decide whether you need a blood test. According to a review on vitamins and hair, iron deficiency is common in women with hair loss, and most authors treat it when it’s confirmed. For zinc or B12, the same review found too little data to recommend supplements for hair loss^[12].

What has no support. The same review concludes that biotin hasn’t been shown to help with telogen effluvium^[12]. It can also throw off some blood tests: if you take it, tell your doctor before any lab work. And too much vitamin A, and probably selenium, can itself cause hair loss^[12]. Taking “hair” supplements without a confirmed deficiency isn’t harmless.

Eating even less isn’t the answer. If the shedding worries you to the point of skipping meals, or if concern about your body leads you to eat very little, reach out for help: your doctor, a therapist or an eating-disorder specialist.

When to see a doctor

Diffuse, temporary shedding after weight loss is the most common pattern, but not the only possible cause. MedlinePlus advises contacting your health care provider if^[13]:

• You’re losing hair in an unusual pattern, or have bald spots, including on your beard or eyebrows. That can be alopecia areata, which isn’t telogen effluvium.
• The scalp is red or scaly, the hair loss comes with pain or itching, or there are areas of infection.
• You’re losing hair rapidly or at an early age.
• You have acne, facial hair or an abnormal menstrual cycle, or you’re a woman with male-pattern baldness.
• You have muscle weakness, intolerance to cold or fatigue.

The thyroid deserves its own mention. Both hypothyroidism and hyperthyroidism can cause telogen effluvium, according to the 2020 review, and it reverses once the thyroid is treated^[8]. Bring it up if, along with the shedding, you notice:

• Feeling cold when others don’t, constipation, dry skin, tiredness or heavier periods (more typical of hypothyroidism)^[14].
• A pounding or racing heartbeat, shaky hands, feeling too hot, nervousness or a goiter, a visibly enlarged thyroid (more typical of hyperthyroidism)^[15].

Some of these symptoms, such as tiredness or constipation, can also come from the GLP-1 medication itself. That’s exactly why it’s worth having a doctor look at them.

If the shedding is heavy or lasts more than 6 months, a dermatologist can look into it. According to MedlinePlus, a careful history and an exam of the hair and scalp are usually enough; blood tests or a scalp biopsy are rarely needed^[13]. Which treatment makes sense for you, if any, is for that dermatologist to decide.

Frequently asked questions

Does Ozempic make your hair fall out?

The US label for Ozempic lists alopecia only among postmarketing reports, with no frequency^[3], and the EU information doesn’t list it at all^[6]. It does appear in the trials of Wegovy, which is semaglutide at higher doses for weight^[1]. The 2026 review points the same way: doses under 2 mg a week were rarely implicated^[7].

Is the hair loss permanent?

With telogen effluvium, usually not. The acute form resolves in about 95% of cases^[8], and with Wegovy most people recovered while staying on treatment^[5]. If you were already prone to hereditary hair loss, the shedding can make it more visible^[7], and that kind doesn’t come back on its own. A dermatologist can tell one from the other.

Should I stop my medication?

That’s a decision to make with your doctor. In the Zepbound trials, no one stopped tirzepatide because of hair loss^[2]. The AAD also warns that stopping a treatment or drug abruptly can cause serious side effects^[16].

Will my hair grow back once my weight levels off?

That’s what you’d expect: acute shedding resolves once the trigger is gone, and the AAD says hair tends to regain its fullness within 6 to 9 months^[16]. The 2020 review notes that a balanced diet and a stable body weight matter^[8]. No one has measured exactly when hair comes back in people on GLP-1 medications.

Does biotin help?

There’s no evidence that it helps with this kind of shedding, and it can interfere with some blood tests^[12]. If your doctor suspects a deficiency, it’s best to confirm it before taking anything.

Is it related to “Ozempic face”?

Both most likely have the same origin: losing a lot of weight. I cover the facial changes in Ozempic face: what it is, why it happens, and what the evidence says.