If you avoid wearing dark clothing because of those tell-tale dandruff flakes, know this.

“Many people believe dandruff is caused by poor hygiene, but this simply isn’t true,” said Dr. Adam J. Friedman, professor and dermatologist at the Albert Einstein College of Medicine. “Rather than try to remedy dandruff by over-shampooing or over-brushing your hair, which can both be damaging to the hair, use dandruff shampoo and scalp treatments instead.”

To get the best results from using dandruff shampoo, Dr. Friedman recommends the following tips:

•  Follow the instructions on the dandruff shampoo bottle. There are many different dandruff shampoos, and each contains different active ingredients for controlling symptoms. For example, some dandruff shampoos require that you lather the shampoo into the hair and onto the scalp and leave on for about 5 minutes before rinsing; others should not be left on the scalp.

•  If you are African-American, only shampoo once a week using a dandruff shampoo. See a dermatologist for the best product recommendation for your hair type.

•  If you are Caucasian or Asian, shampoo daily and use dandruff shampoo twice a week. If using one dandruff shampoo does not bring relief, try alternating between dandruff shampoos with different active ingredients.

•  Be careful when using a dandruff shampoo that contains coal tar. Tar shampoo can discolor blond, gray, or white hair, so if you have light-colored hair, you may want to choose a different dandruff shampoo. In addition, tar shampoo has the potential to make your scalp more sensitive to sunlight. If you use this type of dandruff shampoo, it’s important to protect your scalp from the sun by wearing a hat when outdoors and seeking shade whenever possible.

“For most people, dandruff does not require medical attention,” said Dr. Friedman. “However, sometimes the flaking and itching that appears like dandruff is actually a medical condition, such as seborrheic dermatitis, psoriasis, fungal infections of the scalp, or eczema.” If you continue to have symptoms after using a dandruff shampoo, see your doctor.