Encyclopedia · botanical
Garlic
A 2007 Iranian trial found garlic gel added to a steroid cream improved patchy alopecia areata, but raw garlic is a known skin allergen and nothing supports it for pattern hair loss.
What it is
Garlic is the bulb of Allium sativum. In the trial it was a gel; at home it is usually crushed cloves or garlic oil rubbed on the scalp.
How it works
The mechanism is unknown. Sulfur compounds such as allicin are irritant and antimicrobial, and an immune-modulating effect similar to contact sensitization is speculated.
What the studies show
- In a double-blind trial of 40 people with localized alopecia areata, garlic gel versus placebo gel, both added to betamethasone valerate cream for 3 months, gave a good or moderate response in the whole garlic group, significantly better than control (P=0.001), with no complications reported. Hajheydari 2007
- A systematic review of 16 studies lists topical garlic among the best-evidenced complementary treatments for alopecia areata, with limitations stressed. Tkachenko 2019
The garlic was an adjunct to a corticosteroid, not garlic alone. It is one small trial with no replication, and the concentration was not given in the abstract.
How it's used in studies
A gel applied twice daily for three months together with a steroid cream.
Side effects and safety
Allergic and irritant contact dermatitis to garlic is well documented (Delaney 1996). Raw crushed garlic can also cause chemical burns on skin, and the odor lingers.
Bottom line
Limited evidence for alopecia areata as an adjunct, and no evidence for pattern loss. Do not rub raw garlic on the scalp. If you are tempted, patch-test and talk to a dermatologist about alopecia areata first (see alopecia areata). Discuss with a doctor.
Studies 3
Hajheydari Z et al. Combination of topical garlic gel and betamethasone valerate cream in the treatment of localized alopecia areata: a double-blind randomized controlled study. Indian J Dermatol Venereol Leprol. 2007
Tested: garlic gel vs placebo gel, both with betamethasone valerate cream
Result: Good or moderate response in the whole garlic group, significantly better than control (P=0.001); no complications reported.
Read the study ↗Tkachenko E et al. Complementary and alternative medicine for alopecia areata: a systematic review. J Am Acad Dermatol. 2023
Tested: complementary and alternative treatments
Result: Essential-oil aromatherapy, topical garlic and peony glucosides had the best evidence; adverse events were rare and mild; quality was limited.
Read the study ↗Delaney TA, Donnelly AM. Garlic dermatitis. Australas J Dermatol. 1996
Tested: garlic exposure
Result: Describes allergic and irritant contact dermatitis from garlic.
Read the study ↗Related
- Onion juiceA 2002 Iraqi study found crude onion juice regrew hair in patchy alopecia areata, but the control was tap water, the groups were small, and it was not shown for pattern hair loss.
- Rosemary oilRosemary oil became the internet's "natural minoxidil" from one small 2015 trial that had no placebo group and has never been replicated.
- Alopecia areataAn autoimmune condition where the immune system attacks growing hair follicles, causing round patches or total hair loss; three oral JAK inhibitors are approved for severe cases but hair usually goes again when treatment stops.