Encyclopedia · drug with hair side effects
Lithium
A mood-stabilising medicine whose label lists hair thinning, with figures ranging from no excess in trials to about 1 in 5 in older surveys.
What it is
A first-line mood stabiliser for bipolar disorder, prescription-only in the US, EU and UK, with blood-level monitoring because the safety margin is narrow. It is not a hair treatment.
How it works
No follicle mechanism is established. Two routes are plausible: a direct effect on the follicle, or lithium-induced hypothyroidism, which itself causes diffuse shedding. A meta-analysis found clinical hypothyroidism more likely on lithium than placebo (OR 5.78). McKnight 2012 Lithium also accumulates in hair.
What the studies show
- A meta-analysis of lithium toxicity (385 studies) found no significant increased risk of alopecia or skin disorders. McKnight 2012
- A narrative review states lithium causes hair loss in 12% to 19% of long-term users, with regrowth almost always after stopping or lowering the dose. The review is old and the difference from trial data probably reflects survey methods. Mercke 2000
- In a 1-year observational study in South India, cutaneous side effects occurred in 38.46% of people on lithium, with acneiform eruption and hair fall most common. Suganya 2017
- People who noticed their hair losing curl or wave had higher hair lithium than those with no complaints. McCreadie 1985
- The US label lists drying and thinning of hair and alopecia, without frequency. US label
No controlled trial tested zinc or selenium for lithium-related hair loss.
Side effects and safety
The safety window is narrow, so toxicity (tremor, confusion, kidney effects) needs blood monitoring. Do not start, stop or change lithium to protect hair; abrupt stopping raises relapse risk. Thyroid, kidney and parathyroid effects are recognised. Pregnancy decisions are individual and led by a clinician.
Bottom line
Thinning is real but not universal, and probably less common than older surveys suggest. First check TSH and iron (iron and ferritin; see also antithyroid drugs for how thyroid disease affects hair), then talk to the prescriber. Loss of curl or wave is plausible but poorly quantified. Discuss with a doctor.
Fun facts
- Lithium builds up measurably in hair itself, and the amount tracked with reported loss of curl. McCreadie 1985
Studies 5
McKnight. Lithium toxicity profile: SR and MA. 2012
Result: No significant increased risk of alopecia or skin disorders; clinical hypothyroidism OR 5.78.
Read the study ↗Mercke. Hair loss in psychopharmacology. 2000
Result: States lithium causes hair loss in 12% to 19% of long-term users, with regrowth almost always after stopping or lowering the dose.
Read the study ↗Suganya Priyadharshini et al. Lithium-induced cutaneous side effects, South India. 2017
Result: Cutaneous side effects in 38.46%; acneiform eruption and hair fall most common.
Read the study ↗McCreadie. Lithium and hair texture. 1985
Result: Patients whose hair lost curl or wave had higher hair lithium concentrations.
Read the study ↗Lithium prescribing information. DailyMed. Retrieved 2026-10-10
Result: Lists drying and thinning of hair and alopecia without frequency; lithium concentrates in the thyroid.
Read the study ↗Related
- 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.
- ZincTrue zinc deficiency causes hair loss that zinc fixes, but zinc has not been shown to regrow hair in people who are not deficient, and too much causes copper deficiency.
- 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.
- Hair supplement blends (Nutrafol, Viviscal and similar)Branded multi-ingredient hair vitamins that beat placebo in small, mostly company-linked trials.
- Beta-blockersHeart and blood-pressure drugs that rarely cause reversible shedding, based on old case reports only.