Coal tar is one of the oldest known treatments for psoriasis. It is available over-the-counter without a prescription as a shampoo, gel, and cream.
Coal tar reduces inflammation, slows the rapid growth of skin cells associated with psoriasis, and relieves itching and irritation.
Products that contain a higher concentration of tar are more potent. Most brands, such as T/Gel® and Psoriasin®, contain 2% coal tar. Most OTC preparations do not contain more than 5% coal tar.
Tar can can lead to dry, red and irritated skin. Those starting treatment with coal tar should first apply it to a small area to determine how irritating it is. If tolerable after several days of use, it can be applied to larger areas. If the test area is irritated, one can try applying the coal tar on top of a moisturizer.
Coal tar makes the skin sensitive sunlight, and other forms of UV rays, such as tanning lamps. Those using coal are at increased risk of developing a sunburn for at least 24 hours after its use. It is important to wash it thoroughly off the skin, use sunscreen and minimize your sun exposure.
Some concern about the possible cancer-causing effects of colar tar, but this has been found to occur only in very high concentrations over long periods of time. The FDA has determined that coal tar products with coal tar concentrations between 0.5% and 5% are safe and effective. There is no scientific evidence that the coal tar available over-the-counter is carcinogenic.
Coal tar should be applied with caution because it can stain clothing, bed linen, and light-colored hair.
Use coal tar exactly as directed by your doctor.
Read the medication guide that you receive with the medication for a complete list of possible side effects.
Speak with your doctor if you are concerned about possible side effects that you may be experiencing.