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].

What the FDA labels say

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

US labels checked on October 5, 2026, in the DailyMed versions listed in the sources. 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 severity, recovery and the link to the amount of weight lost, so I use the EU prescribing information for Wegovy only for those. 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, 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].

A 2026 systematic review of 24 studies agrees: semaglutide and tirzepatide had the highest hair-loss rates in the class, and with semaglutide the effect looked dose-dependent, with doses under 2 mg a week, the diabetes doses, rarely implicated. The studies vary widely and some find no higher risk^[7].

The 2026 studies: does tirzepatide cause more hair loss than semaglutide?

Several large health-record studies came out in 2026. They aren’t trials: they compare people who started a GLP-1 with similar people on another treatment and count hair-loss diagnoses.

A risk ratio of 1.77 means 77% more diagnoses than in the comparison group, not that 77% of people lose hair. Only the BMJ study gives absolute numbers: about 2 extra cases per 1,000 people per year, which its authors call a low absolute risk^[19].

What about tirzepatide vs. semaglutide? There’s no reliable head-to-head comparison. The JAAD study pools the two drugs^[17], and the BMJ study looks at the drug class as a whole, only in type 2 diabetes^[19]. The Laryngoscope study compared each with other GLP-1 medications: both were linked to more nonscarring hair loss, and tirzepatide to more telogen effluvium as well, but the abstract gives no figures^[18]. A fourth study, in Archives of Dermatological Research, compares each drug with metformin, but its full text is paywalled and I haven’t been able to check the numbers being shared online, so I don’t repeat them^[20]. And the US label figures (4% to 5% on Zepbound, 3.3% on Wegovy 2.4 mg) come from different trials, with different people and amounts of weight lost, so they can’t settle it either^[1,2]. I cover the other differences in Zepbound vs Wegovy.

What these studies can’t tell you.

• They count diagnoses, not hair. People who never bring it up don’t show up, and there’s no information on how heavy the shedding was or whether it resolved^[17,19].
• They can’t separate the drug from the weight loss. The JAAD authors saw modest weight changes and think weight loss doesn’t explain everything^[17]; the Laryngoscope authors found lower follow-up BMI in people with hair loss^[18]; the BMJ authors consider weight loss and eating less the most likely mechanism^[19].
• There may be bias. People who start a GLP-1 may see their doctor more often and get shedding written down more. The BMJ authors can’t rule that out, and their result weakened after calibration against negative control outcomes^[19].
• A clue to that bias. The JAAD study also found more alopecia areata (risk ratio 1.53 at 1 year), an autoimmune form of hair loss that weight loss isn’t expected to cause; its authors read the pattern as a sign of a drug effect^[17]. Laryngoscope, which used it as a negative control, found no link^[18], and the BMJ study saw no clear one^[19]. My reading, not the authors’: some of the difference in the JAAD study may come from how the groups were compared.

Why hair falls out: telogen effluvium

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

A strong physical stress can push many follicles into the resting phase at once, and 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, 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 brings it on with or without medication:

• In a 2024 Korean 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 retrospective, 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. Telogen effluvium can also unmask hereditary pattern hair loss (androgenetic alopecia) that was already there but not yet visible^[7].

When it starts and how long it lasts

The EU information for Wegovy says most people recovered while staying on treatment^[5]. The longer shedding lasts, the more likely there’s another trigger, such as a nutrient deficiency or a thyroid problem^[8].

Why some people notice it about a year in

Shedding that shows up around the one-year mark, rather than in the first few months, fits how telogen effluvium works: it appears months after the trigger. After childbirth, according to the AAD, shedding starts at about 2 months and peaks at about 4^[16]. On a GLP-1 the weight comes off over months (I go through the curves in how much weight people lose on GLP-1 medications), so if the shedding follows the stretch when you lost the most, it will show up well into the first year. In the JAAD study, the rise in effluvium diagnoses wasn’t clear at 6 months but was at 1 year^[17], though a diagnosis date is the date of the visit, which usually comes later.

If what you notice a year in is a widening part or thinning at the crown, rather than shedding all over, it may be androgenetic alopecia that the effluvium unmasked^[7]. That kind doesn’t recover on its own: according to the AAD, many people with hereditary hair loss keep losing hair without treatment^[16]. Have your doctor or a dermatologist take a look.

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.
• 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, though it considers that this alone doesn’t explain the difference^[7].

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

No trial has tested whether any particular diet prevents hair loss on a GLP-1. What follows makes sense for other reasons and doesn’t replace your doctor.

Eat enough, with enough protein. According to the 2025 joint advisory from four US obesity and nutrition societies, people on these drugs eat 16% to 39% fewer calories, and below 1,200 kcal a day for women or 1,800 for men the risk of falling short on nutrients goes up. For protein, 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 80 to 120 g a day. With a small appetite, the advisory suggests eating the protein-rich foods first and choosing foods that pack a lot of protein into a small volume, such as fish, eggs, Greek yogurt or cottage cheese^[11]. See the protein calculator, protein and muscle on GLP-1 medications, what to eat on GLP-1 medications and 12 high-protein breakfasts for days when you have no appetite.

Deficiencies your doctor can check for. The advisory lists iron, zinc and vitamin B12 among the nutrients to watch and names excessive hair loss among the signs of a deficiency, alongside tiredness beyond what you’d expect and flaky skin^[11]; 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, there’s too little data to recommend supplements for hair loss^[12].

What has no support. According to the same review, biotin hasn’t been shown to help with telogen effluvium, and too much vitamin A, and probably selenium, can itself cause hair loss^[12]. Biotin can also throw off some blood tests: if you take it, tell your doctor before any lab work. 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 concern about your body leads you to eat very little, reach out to 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.

Both hypothyroidism and hyperthyroidism can cause telogen effluvium, which 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].

Tiredness or constipation can also come from the GLP-1 medication itself, which is 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].

Is the hair loss permanent?

With telogen effluvium, usually not: the acute form resolves in about 95% of cases^[8]. If you were already prone to hereditary hair loss, the shedding can make it more visible, and that kind doesn’t come back on its own^[7,16]; a dermatologist can tell them apart.

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].

When does the shedding stop, and will my hair grow back?

The shedding stops once the body readjusts after the trigger, and hair tends to regain its fullness within 6 to 9 months; if weight loss keeps going, the shedding can last longer^[16]. No one has measured it in people on GLP-1 medications: the 2026 studies count diagnoses, not recoveries^[17,19]. If it’s still falling out after 6 months, bring it up with your doctor or a dermatologist.

Does Zepbound or Mounjaro cause more hair loss than Wegovy or Ozempic?

There’s no head-to-head comparison that can answer that. The US labels report hair loss in 4% to 5% of people on Zepbound and 3.3% on Wegovy 2.4 mg, but in different trials^[1,2], and the 2026 studies don’t separate the two drugs reliably^[17,18,19]. The rest of the differences are in Ozempic vs Mounjaro (and Zepbound).

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.