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Article · Vitamins & Ingredients

Rosemary Oil for Hair: What the Research Says

Published Oct 23, 2026 4 min read

The short answer

Does rosemary oil grow hair? Research on rosemary oil for hair is limited to one small human study. That six-month trial included men with pattern hair loss, a 2024 dermatology review reports. Doctors aren't sure how rosemary oil might affect hair, UPMC notes.

Sprig of rosemary with a drop of oil on the leaves

What is rosemary oil?

Rosemary grows as a shrub around the Mediterranean, and the essential oil sold for hair is drawn from its fresh leaves and twigs, UPMC explains. Essential oils are fragrant plant extracts, and a single one can hold more than 100 compounds, according to DermNet.

What does the research say about rosemary oil for hair loss?

The 2024 review says the trial ran in 2015 and randomly assigned 100 men aged 18 to 49 with androgenetic alopecia, the medical name for pattern hair loss. The trial's other group used minoxidil, which the review notes is one of only two medicines the FDA has approved for that condition.

Women weren't included, and the same review notes that pattern hair loss looks different in them: they usually keep their front hairline but thin over the front and center of the scalp. The role of androgens in women's pattern hair loss is also less clear, the review adds.

Why are researchers studying rosemary for hair?

In one study of 300 scalp biopsies from people with pattern hair loss, nearly half showed a buildup of immune cells around the follicles, the 2024 review reports. That finding is why the review's authors see compounds in rosemary that they describe as anti-inflammatory, such as carnosic acid, as worth studying.

What doesn't the research tell us yet?

The best dose and way to apply rosemary oil still haven't been worked out, the 2025 review says. The 2019 review adds that over-the-counter herbal products lack standardized amounts of their active ingredients. A Cleveland Clinic dermatologist says the evidence is still limited.

What are the side effects of rosemary oil on hair and scalp?

Because rosemary oil is concentrated, Cleveland Clinic and UPMC suggest mixing it with a carrier oil, such as coconut or jojoba oil. Putting undiluted essential oils straight on the skin can lead to an allergy, DermNet warns. A reaction can bring itching, redness and scaling, generally 24 to 72 hours after contact, DermNet adds.

Overusing rosemary oil may cause scalp irritation, redness, burning, inflammation or damaged hair follicles, according to Cleveland Clinic. That matters: the 2019 review points out that alternative hair loss products may inflame the scalp and lead to more hair loss.

A few other cautions:

  • Test a small area of scalp first, particularly for people with fine hair or atopic dermatitis (Cleveland Clinic).

  • If you add it to shampoo, choose a gentle, fragrance-free one, since fragrance can raise the risk of irritation (Cleveland Clinic).

  • Keep it out of your eyes, where it can be irritating (UPMC).

  • Rosemary oil isn't recommended during pregnancy or breastfeeding (Cleveland Clinic).

When to talk to a doctor

A receding hairline, a bald spot or overall thinning can signal more than everyday shedding, UPMC notes, and a dermatologist can help figure out why. The 2025 review suggests running any herbal remedy past a healthcare professional first. If your scalp gets irritated, Cleveland Clinic says to stop using the oil and see a dermatologist.

Sources

This article is for education only and is not medical advice. Talk with your healthcare provider about your own hair and scalp health.

Filed underRosemary & Hair Oils

Key takeaways

  1. The best dose and way to apply rosemary oil still haven't been worked out, a 2025 review says.
  2. Because rosemary oil is concentrated, Cleveland Clinic and UPMC suggest mixing it with a carrier oil, such as coconut or jojoba oil.
  3. Test a small area of scalp first, and if your scalp gets irritated, stop using the oil and see a dermatologist (Cleveland Clinic).
  4. Rosemary oil isn't recommended during pregnancy or breastfeeding (Cleveland Clinic).

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