Key points
- Hair loss affected about 3% to 5% of people in the trials, versus about 1% on placebo.
- It's usually temporary shedding linked to fast weight loss.
- Protein, iron and vitamin levels matter.
- Hair usually grows back as weight and eating stabilise.
Is hair loss a side effect?
Some people notice more hair falling out a few months into treatment. In trials, hair loss was reported by about 3% of people on semaglutide 2.4 mg, compared with 1% on placebo (STEP 1), and by about 5% on the highest dose of tirzepatide, compared with about 1% on placebo.
Why it happens
It's thought to be mostly telogen effluvium: temporary shedding that can follow any big change, including fast weight loss, eating much less, illness or stress. It usually starts two to four months after the change, and the hair follicles aren't damaged.
Does it grow back?
Usually, yes. Shedding typically settles over a few months as your weight and eating stabilise, and regrowth follows. If it doesn't, or if you see patches or a receding hairline, see a doctor.
What helps
- Enough protein at every meal: dal, paneer, curd, eggs, chicken or fish.
- Checking iron, vitamin D, B12 and thyroid levels, and treating any deficiency.
- Steady rather than very fast weight loss, which your doctor can manage through your dose.
- Gentle hair care: avoid tight hairstyles and harsh treatments while it settles.
Our lead dermatologist, Dr Anuya Manerkar, helps Lean Life patients with hair thinning and the skin changes that can come with weight loss.
Questions
Does Mounjaro cause hair loss?
Hair loss was reported in about 5% of people on the highest tirzepatide dose in trials, versus about 1% on placebo. It's usually temporary.
Will my hair grow back?
Usually, yes, as your weight and eating stabilise over a few months.
Should I stop the medicine?
Not without talking to your doctor. Often adjusting protein, checking deficiencies or slowing weight loss is enough.
