Does it cause hair loss?

How common

In the Wegovy trials, hair loss was reported by 3.3% on the drug against 1.1% on placebo; on the newer 7.2 mg dose it was 6%, against 3% on 2.4 mg and 1% on placebo.^[1] On Zepbound it was 5%, 4% and 5% at 5, 10 and 15 mg, against 1%. The Zepbound label adds that it was far more common in women: 7.1% of women versus 0.5% of men on the drug. No Zepbound-treated participant stopped the drug because of it.^[2]

Share reporting hair loss, drug vs placebo, from the US labels.^[1][2]

The weight-loss link

Both labels use the same sentence: hair loss "adverse reactions ... were associated with weight reduction."^[1][2] The European product information for Wegovy reports it as more common in people who lost 20% or more of their weight.^[3] A large records study found a higher rate of stress-related shedding with tirzepatide compared with other weight-loss medicines, but not when compared with bariatric surgery, which also causes rapid weight loss.^[3][4] Together this points to the speed and size of weight loss as the main driver, not the molecule itself, though the evidence is observational.

What kind of hair loss

A systematic review found the most common type reported with these drugs is telogen effluvium, a diffuse shed where many hairs enter their resting phase at once after a stressor such as rapid weight loss, surgery or illness.^[4] It typically shows up two to three months after the trigger, continues for a few months and then regrows, according to dermatology reviews; it does not usually cause bald patches.^[3] Some people in the review had pattern hair loss (androgenetic alopecia) that became more noticeable.^[4] Patchy loss, scalp pain or redness are reasons to see a clinician, because they suggest something else.

Heard vs evidence

The short version

Questions to bring to your prescriber

Print these or screenshot them. They are conversation starters, not a checklist of things to do.

• Does the pattern of my hair loss look like stress-related shedding, or something that needs a closer look?
• Could anything else be contributing, such as thyroid, iron or a recent illness, and should we test?
• Is my rate of weight loss something we should talk about?

Sources

Every number on this page traces to one of these. "Primary read" means the full paper or label was read; "abstract only" means only the abstract was available; "secondary" means the figure was taken from a named review.

1. Novo Nordisk / FDA. Wegovy (semaglutide) injection and tablets, prescribing information, revised 06/2026. label
2. Eli Lilly / FDA. Zepbound (tirzepatide) prescribing information, revised 08/2026. label
3. Review: hair loss with GLP-1 receptor agonists, mechanisms and timing. Dermatol Ther 2026. secondary · narrative review
4. Systematic review: GLP-1 receptor agonists and hair loss (telogen effluvium, androgenetic alopecia). 2026. abstract only · systematic review

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