Dandruff treatment: a step-by-step guide

White flakes on your shoulders can be embarrassing, especially in dark clothes. The good news is that dandruff is common, it is not harmful and you cannot catch it ¹. Most people can control it at home with the right shampoo and a little patience.

What dandruff is

Dandruff causes white flakes of skin to appear on the scalp and in the hair. The scalp may also feel dry and itchy ¹. Doctors see dandruff and seborrhoeic dermatitis as part of the same spectrum: dandruff stays on the scalp and causes itchy flaking without visible inflammation, while seborrhoeic dermatitis adds redness and can affect other oily areas such as the face ². See seborrhoeic dermatitis of the scalp.

What causes it?

• Dandruff is not caused by poor hygiene, although it may be more obvious if you do not wash your hair regularly ¹
• A type of yeast that naturally lives on the skin is thought to play a part ¹. DermNet names this yeast as *Malassezia* ³
• Oily skin, sebum, individual sensitivity and the way these interact all contribute ²
• Stress and cold weather can make it worse ¹

Step 1: Pick an anti-dandruff shampoo

Look at the active ingredient, not the brand. Shampoos with one of these ingredients are recommended by the NHS and the American Academy of Dermatology (AAD) ^{1 4}:

• Ketoconazole, an antifungal
• Zinc pyrithione
• Selenium sulfide
• Salicylic acid, which helps lift scale
• Coal tar
• Sulfur (listed by the AAD)

There is no single best shampoo for everyone. You may need to try more than one type to find what works for you ¹. If one stops working, the AAD suggests alternating between shampoos with different active ingredients ⁴.

Step 2: Use it the right way

Anti-dandruff shampoos work on the scalp, not the lengths of your hair.

• Massage the shampoo into the scalp and work up a lather ⁴
• Leave it on for the time stated on the bottle. Some need to stay on for 5 to 10 minutes before rinsing ⁴
• Rinse well, then use your normal conditioner on the lengths if you need it ⁴
• Follow the pack instructions, or ask a pharmacist how to use it ¹

Step 3: Match the routine to your hair type

The AAD gives different advice for different hair types ⁴:

• Fine or straight hair, or an oily scalp: wash often, even daily, and use the dandruff shampoo about twice a week
• Coarse, curly or coily hair: wash when needed and use the dandruff shampoo about once a week, if tolerated. Apply it to the scalp only, as the active ingredients can dry the hair

In Malaysia's heat, many people with oily scalps find more frequent washing comfortable. See how often to wash your hair.

Step 4: Give it time

Use the shampoo for up to 4 weeks to see if your dandruff gets better ¹. DermNet describes using medicated shampoos twice weekly for at least a month, and longer if needed, for the related condition seborrhoeic dermatitis ³. Dandruff often comes back if you stop completely, so many people continue with a lower-frequency routine once flakes are under control.

Step 5: Protect your scalp from the sun

Some dandruff shampoos, such as those with coal tar, can make the scalp more sensitive to sunlight, and sunburn on the scalp can increase flaking ⁴. Under the Malaysian sun, wear a hat or seek shade, especially if your hair is thinning ⁴.

Things that do not help

• Scrubbing hard or scratching can irritate the scalp further. See scalp scrubs and exfoliation
• Heavy oils on the scalp are not a proven dandruff treatment. DermNet explains that the yeast breaks down oils in sebum, which may trigger inflammation ³
• Washing less to "let the scalp breathe" is not needed. Dandruff may simply be more visible when hair is washed less ¹

Is it really dandruff?

Flakes are not always dandruff. The NHS lists other causes of a flaky scalp ¹:

• Seborrhoeic dermatitis: scaly, itchy, red patches on the scalp, face and other areas
• Scalp ringworm (tinea capitis): a red or silver rash, sometimes with patchy hair loss. See scalp ringworm
• Psoriasis: red, flaky, crusty patches covered with silvery scales. See scalp psoriasis
• Contact dermatitis: a reaction to products such as hair dye, sprays or gels
• Eczema, and in babies, cradle cap

If your scalp feels tight and the flakes are small and dry, see dry scalp or dandruff.

When to see a doctor

See a doctor if ¹:

• You still have dandruff after using an anti-dandruff shampoo for at least 4 weeks
• Your dandruff is bad or your scalp is very itchy
• Your scalp is red or swollen
• You have flaky, itchy patches on your face or other parts of your body

A dermatologist may prescribe a stronger shampoo or medicine and can tell whether your flakes are a sign of another condition ⁴.

Does dandruff cause hair loss?

Dandruff itself is not a usual cause of hair loss, but heavy scratching can damage hair, and some causes of flaking, such as scalp ringworm, can cause patchy loss ¹. See the link between dandruff and hair loss.

The bottom line

Choose a shampoo by its active ingredient, leave it on the scalp for the stated time, use it regularly for up to 4 weeks, and switch ingredients if needed. If flakes persist, spread beyond the scalp, or come with redness and hair loss, see a doctor.

Frequently asked questions

Is dandruff caused by not washing my hair?

No. Dandruff is not caused by poor hygiene, though it may be more obvious if hair is not washed regularly ¹.

Which shampoo ingredients treat dandruff?

Ketoconazole, zinc pyrithione, selenium sulfide, salicylic acid, coal tar and sulfur ^{1 4}.

How long before an anti-dandruff shampoo works?

Give it up to 4 weeks. If it has not helped by then, see a doctor ¹.

Is dandruff contagious?

No. You cannot catch dandruff from someone else ¹.

Educational content. Not medical advice.