Encyclopedia · drug with hair side effects
Beta-blockers
Heart and blood-pressure drugs that rarely cause reversible shedding, based on old case reports only.
What it is
A drug class for high blood pressure, angina, heart failure, arrhythmia, migraine prevention, tremor and anxiety. Oral forms are prescription-only; timolol eye drops are used in glaucoma. Never stop a beta-blocker abruptly because of hair loss, as withdrawal can cause rebound heart problems.
How it works
Unknown. Cases look like telogen effluvium: hair loss on metoprolol was confirmed as telogen effluvium on scalp biopsy. Graeber 1981
What the studies show
- Single case: reversible alopecia on metoprolol, with a biopsy showing telogen effluvium. Graeber 1981
- Single case: scalp dermatitis with marked alopecia after 4 months of nadolol, with total regrowth within 3 months of stopping. Shelley 1985
- A review of psychotropic-related alopecia names beta-blockers, lithium and anticonvulsants as most likely to cause drug-related hair loss, which is diffuse, non-scarring and reversible. Warnock 1991
- A review lists alopecia among skin reactions to beta-blockers. Tatu 2019
- A review of 192 common drugs found 13 with strong evidence of alopecia (such as enoxaparin and lamotrigine); beta-blockers were not among them, consistent with a rare reaction. Mounessa 2023
Incidence is unknown. No evidence was found that beta-blockers cause pattern hair loss.
Side effects and safety
Hair loss is minor next to fatigue, slow heart rate, low blood pressure and masking of low blood sugar. Pregnancy use is decided case by case.
Bottom line
If you shed on a beta-blocker, more common explanations come first: iron, thyroid, recent illness or surgery, stress and crash dieting (iron and ferritin, telogen effluvium). Do not stop the drug on your own; a switch is a clinical decision. Discuss with a doctor.
Studies 5
Graeber. Metoprolol and alopecia. 1981
Tested: metoprolol
Result: Reversible alopecia; scalp biopsy showed telogen effluvium.
Read the study ↗Shelley. Alopecia and drug eruption associated with nadolol. 1985
Tested: nadolol
Result: Scalp dermatitis with marked alopecia after 4 months; total regrowth within 3 months of stopping.
Read the study ↗Warnock. Psychotropic medication and drug-related alopecia. 1991
Result: Beta-blockers, lithium and anticonvulsants are most likely to cause drug-related alopecia, which is diffuse, non-scarring and reversible.
Read the study ↗Tatu. Immunologic adverse reactions of beta-blockers and the skin. 2019
Result: Alopecia listed among dermatologic adverse effects of beta-blockers.
Read the study ↗Mounessa. Commonly prescribed medications associated with alopecia. 2023
Result: 13 drugs had strong evidence of an alopecia association, including enoxaparin; beta-blockers were not among them.
Read the study ↗Related
- Anticoagulants (heparin, warfarin, DOACs)Blood thinners that can cause shedding about 3 months after starting, which usually reverses and is never a reason to stop on your own.
- Antithyroid drugs (carbimazole, methimazole, propylthiouracil)Medicines for an overactive thyroid; shedding on them can come from the thyroid disease, an over-treated thyroid, or the drug, which is hard to separate.
- LithiumA mood-stabilising medicine whose label lists hair thinning, with figures ranging from no excess in trials to about 1 in 5 in older surveys.
- Iron and ferritinLow iron stores are common in people who shed hair, but no trial has shown that iron pills regrow hair, and nobody agrees on a hair-specific ferritin target.
- Telogen effluviumA temporary burst of diffuse shedding that starts 2 to 3 months after a physical or emotional shock and usually settles within 6 months once the trigger is gone; it does not cause bald patches.