Patients with refractory autoimmune thrombocytopenia do not respond to standard therapy with high-dose corticosteroids, intravenous immunoglobulin, and splenectomy. We describe the cases of two patients with refractory autoimmune thrombocytopenia treated with oral cyclosporin A (CsA) to evaluate the efficacy of this alternative therapy. Blood pressure and hepatic and renal function were in the normal range before initiation of treatment. Induction therapy with pulses of high-dose methylprednisolone was used for 3 consecutive days to improve the initial immune suppression. Gradual dose reduction of CsA, according the platelet count, minimized the long-term adverse effects of CsA. Oral CsA with pulses of high-dose methylprednisolone induced remission of the thrombocytopenia. Gradual weaning of CsA over months, according the platelet count, produced no observable adverse effects of the CsA. Rapid dose reduction caused thrombocytopenia, which resolved with higher dosages of CsA. Our cases show the efficacy of CsA for refractory immune thrombocytopenia. This therapeutic option with oral CsA as an additional salvage option may avoid splenectomy and the adverse effects of long-term corticosteroids. Larger clinical investigations are necessary to establish the indications and therapeutic regimen for CsA in immune thrombocytopenia.