Seldom Used Drugs for Psoriasis

Before biologic drugs were invented, there were a few drugs that were used for more severe cases of psoriasis, typically when more standard drugs such as methothrexate or Soriatane didn't work. For example:

Cyclosporine

This compound is a protein originally isolated from a soil fungus. It prevents the activation of T-cells that cause inflammation in psoriasis and other diseases. Cyclosporine is still used today quite commonly in organ transplant patients; in fact, it was by accidentally observing improvement in psoriasis in transplant patients that its effectiveness in psoriasis was first discovered. The newer topical drugs Elidel and Protopic are of the same drug class as cyclosporine and work in the same manner.

Cyclosporine is a very fast acting drug which can clear psoriasis in 8 weeks or so. But, unfortunately, the remission times are rather short requiring continuous or frequent short courses of the drug. Because of the kidney toxicity and blood pressure problems caused by cyclosporine, it is not used as frequently in psoriasis as other drugs.

Hydroxyurea

Hydroxyurea was first used for psoriasis in 1970 as an alternative to methotrexate. It is more commonly used by hematologists in the treatment of blood disorders. Hydroxyurea works by preventing the synthesis of DNA, a necessary step in cell duplication which is typically markedly increased in psoriasis. Hydroxyurea is only a moderately effective drug with multiple toxicities which requires extensive monitoring, for this reason it is seldom used for psoriasis.

Sulfasalazine

This sulfa-based anti-inflammatory drug is used as a second-line agent in many inflammatory diseases including inflammatory bowel disease, rheumatoid arthritis and ankylosing spondylitis. It appears to work by decreasing an inflammatory chemical called 5-lipoxygenase. The few studies done on this drug in psoriasis show that only about half of patients respond well to sulfasalazine. Sulfaszalazine has frequent side effects such as headache, nausea and rashes, which many times lead to discontinuation of the drug before any significant benefit has been seen.

Like methotrexate, sulfasalazine can also be useful for psoriatic arthritis. It is sometimes useful as a third-line drug after the other psoriasis pills (methotrexate and Soriatane) and is considerably less expensive than the more effective and more popular biologics. Extensive blood monitoring is required with this drug, although there is little long-term toxicity, such as increased risk of malignancy or infection, seen with some of the other psoriasis systemic medications.
There are other seldom used drugs in psoriasis out there, but they are the really seldom used ones and as such have not been included here.
_{source: Camisa C. Handbook of Psoriasis, 2nd Ed. Blackwell Publishing, USA 2004.}