43 patients (31 men and 12 women), aged 17 to 67 years, affected by moderately severe to severe psoriatic arthritis, were submitted to a discontinuous treatment with oral Cyclosporine A (CyA) (3-5 mg/kg/day). According to the psoriatic arthritis classification by Pigatto et al. 10 patients were affected by oligoarthritis (≤ 4 joints involved) and 33 by polyarthritis (>4 joints involved). All patients showed a different skin involvement, evaluated using PAI index. Assessment of rheamatologic parameters was made at entry and monthly for the first three month of therapy, then the patients were investigated every 3 months. The following laboratory investigations were performed before therapy and monthly: complete blood cell count, ESR, CRP, creatinine, serum urea nitrogen, transaminases, total bilirubin, alkaline phosphatase, electrolytes. The schedule of treatment consisted by an initial dose of 5 mg/kg/day for a period of 1-3 months followed by a maintaining CyA daily-dose of 3-4 mg/kg for 6-12 months. The consecutive CyA cycle were followed by wash-out periods during which patients received steroids (0.1-0.3 mg/kg/day) or etretinate (0.5 mg/kg/day). All patients showed a marked improvement of rheumatologic parameters since 1 month of CyA-therapy and the best results were observed at 3 r d -6 t h month of treatment, as confirmed by statistical evaluation (T-Test). We observed 9 cases of serum creatinine elevation and 5 cases of gingival hiperplasia; all these side effects were transitory and reversible at the stop of CyA therapy.