Dandruff (Seborrhea)

Dandruff (Seborrhea)

What is dandruff (seborrhea)?

It is a common form of skin eczema that occurs in parts of the body with high oil (sebum) production. Body areas  that are commonly affected include the scalp, ears, face, chest, and folds of skin, such as the underarms or the skin below breasts or overhanging abdominal folds. The cause of seborrhea is unknown, although a yeast that often lives on the skin, Malassezia furfur, may play a role.

One common manifestation of seborrhea that affects the scalp is dandruff. Scalp seborrhea can also present as thick, flaky, localized patches of scale. On the face, seborrhea produces reddish-brown, dry-looking, or thick, greasy scales on the eyebrows, sides of the nose, and behind the ears. Reddish, scaly patches may also appear in the folds of skin mentioned above. Although skin affected by seborrhea may feel "dry," moisturizing only makes them redder.
Scalp seborrhea and dandruff do not cause permanent hair loss. Often, scalp seborrhea doesn't even itch significantly. Seborrhea can appear during infancy, starting shortly after birth and lasting several months. It may affect the scalp ("cradle cap") or produce scaly patches on the body. Adults of all ages may develop seborrhea, too, especially on the scalp and face.

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 patches 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, nor is there a "correct" number of times to shampoo per week; 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
• 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, stop and 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.

• Cortisone 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 cortisone creams together with medicated shampoos.

• Anti fungal 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.

If over-the-counter products don't work, what can the doctor prescribe for dandruff?

Your physician or dermatologist can recommend prescription-strength shampoos or antifungal and cortisone creams that are stronger than those available over the counter, yet are not too strong to use on the face. There also are cortisone-based liquids, gels, and foams that you can apply to the scalp that won't leave your hair limp and matted. Nonsteroid cream like tacrolimus (Protopic) or pimecrolimus (Elidel) can also help.
As with all seborrhea (dandruff) treatments, prescription-strength shampoos and cortisone creams calm down your skin or scalp sensitivity, but they can't stop the seborrhea (dandruff) from coming back. Most people, however, only have to treat their condition from time to time when it becomes itchy or noticeable.
A word on eyelashes

Dandruff (seborrhea) of the eyelashes can be both annoying and hard to treat. Eye doctors like to recommend scrubbing the lashes with baby shampoo on a cotton swab. This method may be worth a try, but it often fails. Cortisone-based lotions should be used close to the eye only under medical supervision since continuous exposure of the eye to cortisone can lead to serious eye problems.

Dandruff (Seborrhea) At A Glance

• Dandruff is a form of skin eczema called seborrhea.
• Treatment of seborrhea (dandruff) is directed at fighting the skin inflammation.
• Yeast is a fungus that sometimes builds up on scaly areas of seborrhea.
• The physician may recommend prescription-strength shampoos or antifungal and cortisone creams for seborrhea