Encyclopedia · growth stimulant
Valproic acid (sodium valproate)
A seizure and mood-stabiliser drug that grew hair as a scalp spray in one tiny trial, but taken by mouth commonly causes hair shedding and is a major birth-defect risk.
What it is
Valproate is a prescription anticonvulsant and mood stabiliser. It inhibits an enzyme called GSK3-beta, which stabilises beta-catenin and activates Wnt signalling, a pathway that drives the growth phase of hair (Jo 2013). No topical product is approved for hair. It is prescription-only everywhere.
How it works
In cultured human dermal papilla cells and follicle organ culture, valproate raised beta-catenin, lengthened hair shafts and reduced entry into the regression phase; it also sped growth-phase entry in mice (Jo 2013).
What the studies show
- In a double-blind trial of 40 men (27 completed) with moderate pattern hair loss, an 8.3% sodium valproate spray for 24 weeks raised total hair count more than placebo (P=0.047). Adverse events were mostly mild, and one participant had a ventricular tachycardia judged unrelated. Dropout was high (Jo 2014).
- In mice lacking the Wnt brake CXXC5, valproate further boosted regrowth (Lee 2017).
- No replication of the topical trial has been found since 2014.
How it's used in studies
- 8.3% sodium valproate spray on the scalp for 24 weeks (Jo 2014).
Side effects and safety
- Valproate taken by mouth commonly causes hair abnormalities, such as shedding or curly-hair change, usually benign and reversible (Praharaj 2022).
- Pregnancy: about 1 in 9 babies exposed in the womb has a birth defect and 3 to 4 in 10 may have developmental problems; UK rules require a Pregnancy Prevention Programme for women who could have children (UK guidance). How much a scalp spray is absorbed was not reported, so its risk is unknown. Women who could be pregnant should not use it.
Bottom line
The best evidence is a single small trial, and the molecule is hazardous in pregnancy and a documented cause of hair loss when swallowed, so it is not recommended for hair. Its scientific value is showing that Wnt activation is a workable hair target; see SM04554, which failed. Discuss with a doctor.
Fun facts
- The same drug that thins or curls hair when swallowed was proposed as a hair-growth agent when applied to the scalp (Jo 2014).
Studies 5
Jo SJ et al. Valproic acid promotes human hair growth in in vitro culture model. J Dermatol Sci. 2013
Tested: valproic acid
Result: Raised beta-catenin, lengthened hair shafts and speeded anagen entry in mice.
Read the study ↗Jo SJ et al. Topical valproic acid increases the hair count in male patients with androgenetic alopecia. J Dermatol. 2014
Tested: 8.3% sodium valproate spray vs placebo
Result: Total hair count rose more with valproate (P=0.047); adverse events were mostly mild.
Read the study ↗Lee SH et al. Targeting of CXXC5 by a competing peptide stimulates hair regrowth and wound-induced hair neogenesis. J Invest Dermatol. 2017
Tested: CXXC5-Dishevelled competitor peptide
Result: CXXC5 was raised in balding follicles and the peptide accelerated regrowth in mice.
Read the study ↗Praharaj SK et al. Valproate-associated hair abnormalities. Hum Psychopharmacol. 2022
Tested: oral valproate
Result: Oral valproate commonly causes hair shedding or curly-hair change, usually benign and reversible.
Read the study ↗GOV.UK. Valproate use by women and girls
Tested: valproate
Result: About 1 in 9 babies exposed in the womb has a birth defect and 3 to 4 in 10 may have developmental problems; a Pregnancy Prevention Programme applies.
Read the study ↗Related
- WAY-316606A lab compound that blocks the Wnt brake SFRP1 and lengthened hair in donated human scalp follicles kept alive in a dish; it has never been tested in a person.
- PTD-DBM (CXXC5 competitor peptide)A short peptide that stops the Wnt brake CXXC5 from binding Dishevelled; it sped hair regrowth in mice but has no human data.
- SM04554 (dalosirvir)A topical Wnt-pathway activator tested in about a thousand men with pattern baldness that showed no significant benefit over vehicle.
- Cyclosporine (ciclosporin)A transplant and psoriasis immunosuppressant that makes hair grow as a side effect and works off-label in alopecia areata, but is toxic to kidneys and blood pressure.
- MinoxidilThe most widely used hair-growth treatment, available as a cheap over-the-counter lotion or foam and as a prescription tablet, with a mechanism that is still only partly understood.
- Hair growth pipeline (2026)What is in clinical trials for hair loss as of October 2026, how far along it is, and how much to trust the early numbers.