Seborrhoeic Dermatitis and Dandruff
Flaky, sometimes red and itchy skin on the scalp, eyebrows, sides of the nose, ears and chest. Dandruff is the mild version; cradle cap is the baby version. Not an infection, not contagious, and not a sign of poor hygiene.
Why it happens. It’s thought to be an over-reaction to Malassezia, a yeast that lives on everyone’s skin, in the oily (sebum-rich) areas. It tends to flare with stress, tiredness and cold, dry weather. It’s more common and can be more severe with a weakened immune system (including HIV) and with Parkinson’s disease.
Diagnosis is usually by look alone; tests are rarely needed. On brown and black skin, patches may look lighter or darker than the surrounding skin rather than red, often with fine yellowish flakes. Similar-looking conditions include psoriasis, rosacea and tinea.
The seb derm ladder
There’s no cure, but it’s very controllable. Clear it, then keep it away with a weekly wash.
- Step 1 · Self-careLift the scale firstFor thick scalp scale, massage in an oil or a salicylic acid product, leave it for a few hours, then wash out. Babies: rub in baby oil, then brush gently and wash.
- Works
- Not tested in good trials; makes it easier for shampoos and creams to reach the skin
- Cost
- Free to about $15
- How long
- A few times, then as needed
- Watch for
- Don’t pick or scratch off crusts, especially in babies.
Medicated shampoo can’t treat skin it can’t touch.
- Step 2 · PharmacyAnti-dandruff shampoo (zinc pyrithione, selenium sulfide)Lather into the scalp (and beard or eyebrows), leave for 5 minutes, rinse.
- Works
- Widely used for mild dandruff; fewer good trials than for ketoconazole
- Cost
- About $8–20
- How long
- Every day or two until clear, then once or twice a week
- Watch for
- Selenium can discolour light or chemically treated hair; rinse well.
Five minutes on the scalp, not five seconds on the way to the conditioner.
- Step 3 · PharmacyKetoconazole 2% shampoo or cream (also ciclopirox)An antifungal that calms the yeast. Shampoo for scalp and beard; cream for face and chest.
- Works
- At 4 weeks, about 5 in 10 still had a rash vs 7 in 10 using a dummy treatment
- Cost
- About $12–25
- How long
- Twice a week for 2–4 weeks, then once a week or fortnight to prevent flares
- Watch for
- Mild stinging or dryness. It can dry textured hair: apply to the scalp and condition the lengths.
The weekly maintenance wash is the bit everyone forgets. And then it’s back.
- Step 4 · Pharmacy or prescriptionA short course of mild steroid (hydrocortisone cream, steroid scalp lotion)Calms redness and itch during a flare, alongside an antifungal.
- Works
- Clears flares about as well as ketoconazole in the short term, with more side effects
- Cost
- Pharmacy hydrocortisone: about $8–15. Prescription lotions: under the $25 PBS co-payment
- How long
- Days to 2 weeks, then stop
- Watch for
- Thinning skin and perioral dermatitis with long use on the face.
A fire extinguisher, not a lifestyle.
- Step 5 · PrescriptionNon-steroid creams (pimecrolimus, tacrolimus) or antifungal tabletsFor the face when steroids keep being needed, or for severe, widespread flares.
- Works
- Small trials suggest they help; tablets are for hard cases only
- Cost
- Varies; often a private script
- How long
- Weeks, then as needed
- Watch for
- Burning at first with the creams. Tablets need a check of other medicines and sometimes liver tests.
For when the basics have genuinely been tried, not briefly flirted with.
- Step 6 · SpecialistDermatologistFor severe or unusual rashes, or when the diagnosis isn’t clear.
- Works
- No trials of referral itself; useful when it isn’t behaving like seb derm
- Cost
- Specialist fees vary; Medicare rebates with a GP referral
- How long
- One to a few visits
- Watch for
- Bring a list of every shampoo and cream you’ve tried.
Sometimes the plot twist is that it was psoriasis all along.
Save your money
Popular, heavily marketed or often asked about, but the evidence is weak or says no.
- Apple cider vinegar rinsesNo trials for seb derm, and it can sting broken skin. Salad, not scalp.
- Special diets and supplementsNo good evidence any diet or supplement prevents flares.
- Premium “clinical” shampoosPrice isn’t the active ingredient. Check the label for ketoconazole, zinc pyrithione, selenium sulfide or ciclopirox.
- Washing your hair less to “let the scalp rebalance”Oil and scale build up and feed the flare. Regular washing with the right shampoo helps.
What you can do
- Keep using an antifungal shampoo once a week or fortnight after it clears.
- Beards count: wash them with the medicated shampoo too, or trim short in a flare.
- Use a gentle, fragrance-free cleanser and moisturiser on the face.
- Expect flares with stress, illness and winter, and restart treatment early.
See your GP if
- It isn’t improving after 4 weeks of pharmacy treatment
- The rash is spreading, weeping or very itchy
- Your baby’s cradle cap is red, spreading, weeping or itchy, or they seem unwell
- It came on suddenly and severely, or you have other new symptoms
See a doctor promptly if a baby with a rash has a fever, isn’t feeding or seems unwell, or if skin becomes hot, swollen and painful, which can mean infection.
Common questions
Is dandruff the same as seborrhoeic dermatitis?
Pretty much. Dandruff is the mild, flaky, non-inflamed end of the same condition.
Is it caused by poor hygiene?
No. It’s an over-reaction to a yeast that lives on everyone’s skin. It’s not contagious.
Will cradle cap go away?
Yes, usually within 6 to 12 months without treatment. Softening the crusts with oil and washing gently is all most babies need.
Why does it keep coming back?
It’s a long-term tendency, not a one-off infection. A weekly antifungal wash after it clears is the best way to keep it away.
Helpful resources
- Healthdirect: Seborrhoeic dermatitisAustralian Government guide covering adults and babies with cradle cap. Free.
- British Association of Dermatologists: Seborrhoeic dermatitisPatient leaflet from UK skin specialists, including how it looks on different skin tones. Free.
Evidence and more information
- Healthdirect: Seborrhoeic dermatitis
- British Association of Dermatologists: Seborrhoeic dermatitis
- Cochrane: Topical antifungals for seborrhoeic dermatitis (2015)
maladywise.com/seb-derm/