Last updated 25 August 2026 · Originally published 27 July 2020
CBD scalp products come in two broad kinds: serums and oils that claim to regrow hair, and shampoos that claim to calm an itchy, flaky or inflamed scalp. The evidence consists of two uncontrolled hair-growth case series from the same clinic and one uncontrolled shampoo study. All three reported good results. None can tell us whether CBD caused them.
The hair-growth studies
In 2021, a Florida hair clinic gave 35 people with pattern hair loss a CBD-rich hemp formulation delivering roughly 3 to 4 mg of CBD a day, rubbed into their thinning areas for six months. Hair counts went up by an average of 93.5%. A follow-up in 2023 tested a higher-dose hemp extract containing CBD, THCV and CBDV, together with menthol, peppermint oil and emu oil. All 31 participants recorded some regrowth. Because there was again no control group, and several ingredients changed, the study cannot show which ingredient, if any, produced the result.
Those are striking numbers, and they were widely reported as a breakthrough. The problem is the design. There was no comparison group: everyone received the product, and the results were measured only against where they started. Hair was counted in a small selected area, without blinded assessors or an untreated group. Measurement variation, natural changes and the effects of the other ingredients therefore cannot be separated from a cannabinoid effect. The same clinic ran both studies, and the second was registered on a public trials database, which press releases turned into “an NIH clinical study”. It was not.
There is also a wrinkle in the biology. A 2007 study found that activating CB1 receptors inhibited growth in cultured human hair follicles. CBD does not simply activate CB1 in the same way, but its own effects appear to depend on concentration. In a 2020 laboratory study, a very low concentration tended to promote hair-shaft elongation, while a much higher concentration inhibited growth and pushed follicles towards the regression phase. That makes a simple “CBD stimulates hair” mechanism difficult to defend.
The dandruff and psoriasis study
The shampoo evidence is a 2020 study of 50 people with mild to moderate scalp psoriasis or seborrheic dermatitis, the condition behind most stubborn dandruff. After two weeks using a shampoo containing 0.075% CBD, redness, scaling, itching and burning all fell substantially, and dermoscopy showed less inflammation.
Two things the abstract does not lead with. The shampoo also contained ketoconazole, an established antifungal treatment for seborrheic dermatitis that could account for many of the improvements in that group, along with other active ingredients. And the study was funded by the shampoo’s manufacturer, with the senior author a consultant to the company. With no comparison group, there is no way to know what the CBD added to the complete formulation, if anything.
A separate confusion: hemp seed oil
Many “CBD” hair products lean on the fatty acids and vitamin E in hemp oil. Those are real, and they can work as conditioning and emollient ingredients, but they come from hemp seed oil, which naturally contains essentially no CBD. A product can be rich in them and contain almost no cannabidiol, and a product can contain plenty of CBD and none of them. If the benefits listed on the bottle are nutritional, you are being sold hemp seed oil at CBD prices. We set out the difference separately.
What that leaves
We could not find a placebo-controlled trial of a CBD scalp product for hair growth, dandruff or scalp psoriasis. That does not mean CBD does nothing there. Skin does carry the receptors, CBD applied to skin does stay largely in the skin, and its anti-inflammatory effects in the laboratory are real. “Plausible and untested” is the honest description, and it is a weaker one than the products suggest.
If you have scalp psoriasis or persistent dandruff, established options include antifungal shampoos for seborrheic dermatitis and medicated shampoos or topical corticosteroids for scalp psoriasis. The two conditions can look similar but need different treatment, so persistent symptoms are worth showing to a doctor. A CBD shampoo that also contains one of those may well help. Whether the CBD adds anything is a fair question that has not yet been answered. There is a plausible reason to investigate it, since CBD has anti-inflammatory effects in skin models, but plausibility is not proof that a shampoo works.
If you want to try a CBD scalp product anyway, the same rules apply as for any CBD topical. Check the certificate of analysis so the CBD is actually there, since topicals are the worst-labelled category of CBD product. Patch-test it. Read the ingredients list so you know what else is in it and can judge what is doing what. And if a product quotes the 93.5% figure, you now know where it came from.
Nothing in this article is medical advice. Persistent hair loss or scalp inflammation is worth a visit to a doctor or dermatologist, who can rule out causes that need treatment.
