Also, cyclosporine is not recommended for patients who have a weak immune system, those who have had substantial exposure to UVB or PUVA in the past, or those who are pregnant or breast-feeding. Compared with methotrexate and cyclosporine, hydroxyurea is less toxic but also less effective. Possible side effects include anemia and a decrease in white blood cells and platelets. Like methotrexate and cyclosporine, hydroxyurea must be avoided by pregnant women or those who are planning to become pregnant. Because this treatment also may cause birth defects, women must protect themselves from pregnancy beginning 1 month before through 3 years after treatment.
Most patients experience a recurrence of psoriasis after acitretin is discontinued.
Although not indicated in routine treatment, antibiotics may be employed when an infection, such as Streptococcus, triggers the outbreak of psoriasis, as in certain cases of guttate psoriasis. Researchers continue to search for genes that contribute to the inherited and other causes of psoriasis. Scientists are also working to improve our understanding of what happens in the body to trigger this disease. In addition, much research is focused on developing new and better treatments. Some of these experimental treatments, such as agents directed at the specific types of T cells involved, work to improve the disease with less overall suppression of the immune system.