Can you use benzoyl peroxide on your scalp?

Which scalp bumps can it help?

Benzoyl peroxide kills acne bacteria on the skin and inside hair follicles. It is also used for some forms of folliculitis, meaning inflammation around hair follicles. But scalp bumps are not automatically acne: yeast, bacteria, product buildup and other scalp conditions can be involved. Treatment depends on the cause, so persistent bumps need an assessment rather than a stronger tube.12

How should you apply it?

Benzoyl peroxide comes in creams, lotions, gels and cleansing products. A wash is rinsed off; a leave on gel remains on the skin, which makes the names unusually informative for skincare. The steps below are general benzoyl peroxide directions, not a separate scalp dosing schedule. Follow the directions for the product your pharmacist or clinician considers suitable.34

1. 1Start with the lowest available strength. A 2.5% formula can reduce irritation compared with higher concentrations.
2. 2For first use, apply a small amount to one or two small treatment areas for three days. Continue only if there is no reaction or discomfort.
3. 3Wash your hands. For a wash, wet the affected skin, use a small amount and rinse as directed. NHS gel wash directions specify washing for one to two minutes before rinsing.
4. 4For a leave on gel, gently clean and dry the affected skin, then apply a thin layer. Wash your hands afterwards.
5. 5Start once daily unless your prescription or product instructions say otherwise. Do not increase the amount or frequency to speed up results.

Will it bleach your hair?

Benzoyl peroxide can bleach hair and coloured fabrics. Keep the medicine off hair, clothing, towels and pillowcases. That warning makes scalp application less straightforward than application to exposed skin: if you cannot keep the product away from your hair, ask about another treatment rather than assuming a rinse will prevent bleaching.4

What else should you change?

For mild scalp pimples, stop greasy hair products or products that leave residue, and wash your hair more often, especially after sweating. Avoid tight headbands and hats, which gives the hair care routine an unexpected interest in millinery. Wash hats and pillowcases regularly to remove product residue, because neither item signed up to be a styling product, especially one without its own bottle. Do not pop or scratch bumps: this can cause scarring or infection.1

How long does it take?

For acne generally, benzoyl peroxide takes about four to six weeks to show an effect. Scalp acne can improve within days after appropriate treatment or removal of a triggering hair product, but clearing can take up to six weeks. Contact a clinician if your scalp has not improved after six weeks. Deep acne nodules or cysts need a dermatologist because they can leave permanent scars.145

When should you stop or get help?

• Mild dryness or peeling can improve with less frequent use. Ask a pharmacist or doctor if irritation persists.
• Stop and get prompt medical advice for burning, blistering or marked redness. Get emergency help for breathing difficulty, throat tightness, faintness or facial swelling.
• Do not apply it to cuts, grazes or infected skin. Keep it away from eyes, nose and mouth. Protect exposed treated skin from sunlight.
• Seek care for worsening scalp bumps, severe pain or swelling, or fever.
• Check before combining it with other acne medicines, especially treatments that dry or irritate skin. During pregnancy or breastfeeding, check with a pharmacist or doctor before starting.

How should you store it?

Follow the package storage instructions and keep benzoyl peroxide away from excess heat. For people concerned about benzene formation, the American Academy of Dermatology advises replacing products every 10 to 12 weeks and discarding products exposed to temperatures above 78°F.6