Dandruff and Seborrheic Dermatitis: Causes and Treatment
Part of: Hair & scalp
Why dandruff appears and comes back, how it differs from seborrheic dermatitis, which shampoo ingredients to look for, how to use them for your hair type, and when you need prescription treatment.
Scalp · 3 min read · August 22, 2026
Written and medically reviewed by Dr. Yousef Abo Zarad · German board-certified dermatologist · Last reviewed: September 2026
Key takeaways
- Dandruff is the mild form of seborrheic dermatitis, a common inflammatory condition causing greasy or dry scale and itch in oily areas.
- It is not caused by poor hygiene; it is linked to a yeast (Malassezia) that normally lives on the skin.
- A dandruff shampoo is enough for many mild to moderate cases; what matters is the right ingredient and leaving it on the scalp for a few minutes.
- It is managed rather than cured: it settles with treatment and can return with stress and cold weather.
What is seborrheic dermatitis?
It is a chronic skin inflammation that appears as a scaly rash in areas rich in oil glands. Scale can be dry, greasy or both, and may come with itch or burning.
On lighter skin it looks red and slightly raised; on darker skin it may look pink, slightly purple, or lighter than the natural skin tone.
Where does it appear?
- Scalp: dandruff is its best-known form.
- Face: forehead, eyebrows, eyelids, sides of the nose and around the mouth.
- Ears and the back of the neck.
- Chest, and in extensive cases the armpits, groin and skin folds.
- In babies: cradle cap on the scalp, sometimes in skin folds or the diaper area.
What causes and triggers it?
There is no single known cause, but Malassezia, a yeast that normally lives on the skin, plays an important role.
- Stress.
- Cold, dry weather and hot showers in winter.
- Harsh soaps, detergents and chemicals.
- Heavy sweating.
- Skin and hair products that contain alcohol.
Dandruff shampoo ingredients: what to choose
| Ingredient | Notes |
|---|---|
| Ketoconazole 1% | Antifungal; one of the most used options for scalp, face and beard |
| Zinc pyrithione | A common option for regular use; also found in medicated facial cleansers |
| Selenium sulfide | Antifungal and anti-scale |
| Salicylic acid | Helps remove thick scale |
| Sulfur | Among the recommended dandruff ingredients |
| Coal tar | Effective, but can discolor light or treated hair and makes the scalp more sun-sensitive |
How to use dandruff shampoo correctly
- Massage it into the scalp itself and leave it on for 5 to 10 minutes before rinsing if the label says so.
- Fine, straight hair or an oily scalp: wash daily and use dandruff shampoo twice a week.
- Curly or coarse hair: wash as needed and use dandruff shampoo about once a week on the scalp only, so the hair does not dry out; follow with regular shampoo and conditioner if you like.
- Beard and moustache: wash with a 1% ketoconazole shampoo, or keep the area shaved.
- With coal tar, protect your scalp from the sun with a wide-brimmed hat and a water-resistant SPF 30+ sunscreen.
Face and skin care
- Wash your face twice a day with a gentle or zinc-pyrithione cleanser, and avoid fragranced soaps.
- Choose alcohol-free products: moisturizer, sunscreen, conditioner and makeup.
- Use a sunscreen with zinc oxide or titanium dioxide.
- Treat flares early and keep a note of your triggers so you can avoid them.
Treatment from a doctor
If shampoo is not enough, a dermatologist prescribes treatment according to the site and severity.
- Topical antifungals: ketoconazole cream, gel or foam, and prescription ciclopirox shampoo.
- A short course of topical corticosteroid to calm inflammation and redness quickly.
- Roflumilast foam from age 9, a newer non-steroid treatment.
- Topical calcineurin inhibitors (pimecrolimus, tacrolimus) for the face and eyelids.
- For widespread disease: oral antifungals or light therapy.
Cradle cap in babies
Dandruff shampoo is not recommended for children. Care involves baby shampoo and gently removing the scale; it usually clears within weeks to months.
When to see a doctor
- Dandruff that persists despite using a dandruff shampoo correctly for several weeks.
- Severe dandruff, or a rash spreading to the face and body.
- If you suspect something else: psoriasis, scalp fungal infection and eczema can look similar and each needs different treatment.
Common questions
- Is dandruff caused by poor hygiene? No. It is linked to a normal skin yeast and inflammation, and can worsen with stress and cold.
- Should I wash more often? How often depends on hair type; what matters is using the dandruff shampoo correctly and leaving it on the scalp.
- Will it go away for good? It is usually managed rather than cured, so keep using the shampoo as maintenance after it improves.
Key numbers
- Straight hair: dandruff shampoo two to three times a week; curly hair: once a week.
- In a roflumilast foam study, most patients had clear or almost clear skin within 8 weeks.