• Biologics: These drugs, usually administered by injection, alter the immune system in a way that disrupts the disease cycle and improves symptoms and signs of disease within weeks. Several of these drugs are approved for the treatment of moderate to severe psoriasis in people who haven't responded to first line therapies.
Biologics must be used with caution because they carry the risk of suppressing the immune system in ways that increase the risk of serious infections. People taking these treatments must be screened for tuberculosis.
• Methotrexate: Usually administered weekly as a single oral dose, methotrexate (Trexall) decreases the production of skin cells and suppresses inflammation. It's less effective than adalimumab and infliximab. It might cause upset stomach, loss of appetite and fatigue. People taking methotrexate long-term need ongoing testing to monitor their blood counts and liver function.
• Cyclosporine. Taken orally for severe psoriasis, cyclosporine (Gengraf, Neoral, Sandimmune) suppresses the immune system. It's similar to methotrexate in effectiveness but cannot be used continuously for more than a year. Like other immunosuppressant drugs, cyclosporine increases the risk of infection and other health problems, including cancer.
•Other medications. Thioguanine (Tabloid) and hydroxyurea (Droxia, Hydrea) are medications that can be used when you can't take other drugs. Talk with your health care provider about possible side effects of these drugs.
Courtesy: Mayo Clinic