Common Triggers for Dandruff

Dandruff is characterized by thin flakes on the scalp. While not a concerning health problem, it can be embarrassing.

The possible causes include:

• Dry skin.
• Oily, greasy skin (seborrheic dermatitis).
• Insufficient shampooing of the scalp.
• Eczema, psoriasis and other skin conditions, which may resemble dandruff.
• A fungus called malassezia.
• Contact dermatitis, caused by a sensitivity to certain skin and hair products.

What treatments are available for dandruff?

Treatment of seborrhea (dandruff) is directed at fighting the skin inflammation. This is done either directly, by using cortisone-based creams and lotions (which reduce inflammation), or by reducing the yeast that builds up on scaly areas and adds to the problem. 

Note, though, that seborrhea is not a yeast infection.

What doesn't help dandruff?

• Moisturizing: Moisturizing lotions don't do much more than smooth out scales and make plaques look redder.
• Switching brands of shampoo: Shampoo doesn't cause dandruff. However, medicated shampoos (see below) can help.
• Changing hair-care routines: There is no "right" shampoo or conditioner. What is more important is the frequency with which these agents are used. As a rule, the more frequently one shampoos, the better the result. Seborrhea and dandruff are not caused by excessive shampooing "drying out the scalp." Hair dyes and conditioners do not cause or aggravate dandruff.
• Switching antiperspirants: When underarms are red from seborrhea, almost anything will make them redder, including antiperspirants, even though they are only aggravating the seborrhea and not causing it.

What over-the-counter products can help dandruff?

1. Shampoos: Here are some ingredients in medicated shampoos that you can look for to help control dandruff of the scalp. All are available over the counter.
   • tar (T/Gel)
   • salicylic acid (T/Sal)
   • zinc pyrithione (like Head & Shoulders)
   • selenium sulfide (Selsun Blue)
   • ketoconazole (Nizoral)
   You can use any of these either all of the time or just once or twice a week, depending on how severe your symptoms are. If the problem quiets down or disappears, your can use nonmedicated shampoos. If one kind of shampoo works for a while and "runs out of gas," switch to another. For resistant cases, you can even alternate two different types.
2. Creams: Two additional types of medication that help seborrhea are cortisone creams and antifungal creams.
   • Corticosteroid creams reduce inflammation. You can buy them over the counter in either 0.5% or 1% concentrations. They are safe to use on the face and will often help in just a couple of days when applied twice daily. These products also are available as scalp lotions that are applied once a day, preferably on damp hair after shampooing. You can use scalp corticosteroid creams together with medicated shampoos.
   • Antifungal creams are often effective, apparently because they reduce the number of yeast organisms living on the skin. Over-the-counter creams include 1% clotrimazole cream and miconazole cream 2%. Antifungal creams also are applied once or twice a day.

As with shampoos, creams should be applied until the seborrhea subsides. 

When the seborrhea comes back (and it will, sooner or later), the creams should be used again.