Does rosemary oil work for hair growth?

Short answer: promising, but one small trial

The best human evidence we found is a single randomized trial in men with androgenetic alopecia, the common pattern hair loss. Over six months, rosemary oil and 2% minoxidil produced similar hair counts. That is encouraging, but it is one study, and it does not make rosemary oil a proven treatment.

The trial, published in Skinmed in 2015, randomly assigned 50 men to rosemary oil and 50 to 2% minoxidil (trial abstract). Neither group changed at three months. Both improved significantly by month six, and the gap between groups was not significant at either checkpoint.

What the 2015 trial measured and where it falls short

The main outcome was hair count, and rosemary oil did not beat minoxidil on it. The one difference that stood out was side effects: scalp itching was less frequent in the rosemary group, according to a review of hair loss treatment options.

Masking was weaker than in a double-blind design. A separate overview of natural alternatives describes the trial as single-blind and limited to men aged 18 to 49. Results may not carry over to women or to older men.

The protocol reportedly used 2 mL of oil massaged into the frontoparietal and vertex scalp, according to a systematic review of herbal remedies. We could not confirm how often it was applied or what carrier was used, so check the full paper before copying the routine.

Newer studies don't settle the question

Most of the newer work is small or tied to a product. Each one tells you something different, and none of them isolates rosemary oil the way a head-to-head trial would.

• Rosmagain, a rosemary-lavender and rosemary-castor oil product, was tested in a 90-day, double-blind, three-arm trial. Hair growth rose about 58% and 48% from baseline. The comparator was coconut oil, not minoxidil, and the sponsor and sample size were unclear in the version we read (Rosmagain trial).
• Tetragain, a multi-ingredient serum that includes rosemary oil, was tested in an open-label, single-arm study of 32 women, with 30 completing it. Without a control arm, it cannot separate rosemary's effect from the other ingredients or from natural regrowth (Tetragain study).
• A 1998 double-blind trial of 86 people with alopecia areata used a mix of four essential oils, including rosemary, in carrier oils. The control group got carrier oil alone. Because rosemary was one of four oils, the trial cannot isolate its effect (Hay et al. trial).
• A 2024 animal and formulation study found that a rosemary oil microsponge gel outperformed a rosemary gel and minoxidil in hair length, thickness and bulb diameter. That comparison is to an engineered formulation, not plain rosemary oil, and the abstract does not name the animal model (microsponge study).

Greying claims are an association, not a cure

A Saudi cross-sectional study reported that rosemary oil use was associated with at least 38% lower odds of hair greying, with an adjusted odds ratio of 0.618. That describes an association, not proof that rosemary prevents grey hair. The authors also noted that rosemary use may have been too short to detect real changes (greying study).

How to think about trying it

If you want to try rosemary oil, go in with realistic expectations. It is cheap, and the trial data suggest it may be tolerated, but we found no standard concentration or schedule across studies.

We also did not find position statements from dermatology societies or the FDA on rosemary oil in our searches. That means we found no guidance, not proof that none exists. Sudden or patchy shedding is a reason to see a clinician, and minoxidil remains the comparator with far more evidence behind it. For the broader picture, see our rosemary oil topic page.