Selenium sulfide is an anti-infective agent used as a shampoo to relieve itching and flaking of the scalp. In people prone to dandruff, an uninflamed form of seborrhoeic dermatitis, the fungus Malassezia can cause irritation, itching and increased shedding of dead skin cells in areas of the scalp. This shedding may occur every 5 days rather than once a month as it would in people without dandruff.
Selenium sulfide treats the excess shedding and irritation by eliminating excess scalp fungus and controlling the rate of shedding of dead skin cells.
In addition to controlling the symptoms of dandruff, selenium sulfide is also used to treat pityriasis versicolor, a fungal infection of the skin and tinea captis, a fungal infection of the scalp.
Selenium sulfide preparations
Selenium sulfide is available as a 1% and 2.5% lotion and shampoo. Some commonly used brand names are Selsun®, Exsel® and Head & Shoulders Intensive Treatment®.
Low strength selenium sulfide preparations are available from your pharmacy or supermarket. In some countries, higher strength preparations are only available on a doctor's prescription.
How to use selenium sulfide preparations
It is very important that you use selenium sulfide preparations strictly as directed on the label or as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than recommended.
- Wet hair and scalp with lukewarm water
- Apply enough selenium sulfide shampoo to the scalp to work up a lather
- Allow lather to remain on scalp for 2-3 minutes before rinsing off
- Repeat with a second wash then rinse well
- Wash hands well and clean under nails to remove any shampoo
- Use 1% or 2.5% shampoo twice a week for the first 2 weeks, then once weekly for 2, 3 or 4 weeks, and then only when necessary
For skin infections:
- Apply selenium sulfide lotion to affected areas of the body (do not apply to face or genitals)
- Work up a lather using a small amount of water
- Allow the medicine to stay in contact with your skin for about 10 minutes
- Rinse body well to remove all the medicine
- Use the 2.5% lotion once per day for 7 days
Do not use if your scalp or the skin to be treated is cut or scratched. Do not leave on hair, scalp or skin for periods longer than directed and ensure all selenium sulfide is rinsed off well.
Avoid getting selenium sulfide in your eyes. If accidental contact with eyes occurs, rinse them well with clear water for several minutes.
Selenium sulfide preparations are usually well tolerated. Stop using the preparation and check with your doctor if you experience scalp irritation or skin irritation.
Other side effects that may occur include:
- Unusual oiliness or dryness of hair or scalp
- Increase in normal hair loss
- Hair discolouration
See your doctor if these effects are severe or do not go away.
Selenium sulfide can be used safely on the scalp in pregnant women. It should not be used on the body to treat skin infections if you are pregnant as selenium sulfide may be absorbed through the mother’s skin.