Treatment decisions
Seborrhoeic dermatitis: what to try, in order
Several treatments work and none cures it. The useful question is the sequence — what to start with, how long to give it, and what to change to.
- Start with ketoconazoleThe largest evidence base, 21 skin studies
- Give it four weeksSeveral minutes of contact, twice weekly
- Then keep going weeklyStopping entirely is what brings it back
On this pageWhat you are treating5
Quick answer
The bottom line
Start with an antifungal shampoo — ketoconazole has the most published evidence, with 21 skin studies — used two or three times a week with several minutes of contact time before rinsing. Give it four weeks before judging, and if it has not controlled the flaking, change the active rather than the brand: selenium sulfide, zinc pyrithione and coal tar all have a place. For the face, a short course of a mild anti-inflammatory from a clinician settles a flare that shampoo alone will not reach. Expect to keep treating at a lower frequency once it settles, because stopping entirely is what brings it back.
At a glance
Three things worth remembering
Section 01
What you are treating
Seborrhoeic dermatitis is an inflammatory reaction to a yeast that lives on everyone’s skin, concentrated where oil glands are densest: the scalp, the sides of the nose, the brows, behind the ears and sometimes the chest. It produces greasy yellowish flaking on a red base, and it itches more than it hurts.[1][5]
Because the yeast is normal flora, treatment reduces its numbers and calms the reaction rather than eliminating a foreign invader. That is the reason every effective treatment needs continuing, and why it reliably returns weeks after stopping.[1][5]
Section 02
The sequence worth following
The reason to change active rather than brand is that most shampoos in a category contain the same handful of approved ingredients at similar strengths. Two ketoconazole shampoos from different brands are close to the same treatment; ketoconazole and selenium sulfide are genuinely different.[3][4]
| Step | What to use | How long before changing |
|---|---|---|
| First | Ketoconazole shampoo, 2 to 3 times weekly | 4 weeks[2][4] |
| Second | Switch active: selenium sulfide or zinc pyrithione | 4 weeks[3][4] |
| Third | Add coal tar or salicylic acid for thick scale | 4 weeks[3][1] |
| Face or resistant | See a clinician for a short anti-inflammatory course | Review at 2 to 4 weeks[1] |
| Maintenance | Same active, once weekly, ongoing | Indefinitely[1][5] |
Section 03
The technique that decides whether it works
- Apply to the scalp skin, not the hair. Part the hair in sections and work it in with fingertips.[1][2]
- Leave it on for at least three to five minutes. Most treatment failures we see described are rinsing immediately.[2][1]
- Two or three times a week is the usual treating frequency; daily is not better and dries the scalp.[3]
- For the face, use the shampoo as a short-contact wash on affected areas if the label allows, and rinse thoroughly.[1]
Section 04
The face needs a different answer
Facial seborrhoeic dermatitis around the nose and brows often will not settle with shampoo alone. A clinician can prescribe a short course of a mild topical steroid or a non-steroid anti-inflammatory to break the flare, then hand back to an antifungal for maintenance. That two-stage pattern is the standard approach and it works well.[1]
What matters is that facial steroids are used briefly and under direction. Long unsupervised use thins the skin and causes a rebound redness that is harder to treat than the original problem. This is a genuine reason to get the prescription rather than borrow a tube.[1][5]
Section 05
When it needs looking at
Thick, well-defined silvery plaques with a sharp edge are more likely psoriasis, which has a different treatment ladder. Scaling that appears suddenly and severely in an adult, or that comes with hair loss, weight loss or other symptoms, deserves prompt review rather than another shampoo.[1][5]
In infants, cradle cap looks similar and behaves differently — it usually clears on its own and needs gentle handling rather than medicated shampoos. Ask before treating a baby with an adult product.[1]
Your next step
Turn this into a practical plan
Choose the guide that best matches what you see. Each one starts with what to try, how long to wait and when to get help.