ABSTRACT
Tar shampoos are some of the most effective cleansers in seborrheic dermatitis. This is because tar is a naturally occurring anti-inflammatory agent. By definition, antiinflammatory agents decrease the white blood cell population in a given skin area. Inflammation in the skin always occurs for a reason, but the dermatologist may not be able to determine the cause. Many skin conditions are treated with antiinflammatory agents nonspecifically without understanding the etiology. Psoriasis and seborrheic dermatitis are excellent examples. Anti-inflammatories can only control symptoms and not produce a cure. While chasing the white blood cells out of the skin with tar in seborrheic dermatitis produces remission of the scaling and itching associated with the condition, it is also a carcinogen for the same reason. The carcinogenicity of tar has been a source of controversy discussed on some consumer websites. Tar is a carcinogen, but purified tar with the creosote removed is less of a carcinogen. The newer dandruff shampoos use purified tar because it does not stain fabric washcloths, it has a more pleasant odor, and it is less of a carcinogen. Interestingly, it is also less effective in treating seborrheic dermatitis.
