We tried to use antilymphocyte globulin (ALG) and antithymocyte globulin (ATG) in 2 severe cases of aplastic anemia. ALG was administered to a 58 year-old male patient, and ATG was administered to a 23 year-old male patient. Both of them had shown severe pancytopenia and bone marrow hypoplasia before the treatment. They responded to the ALG or ATG therapy, and reached complete remission in 8 months and in 4 months, respectively. They have maintained complete remission up to now without any treatment. Adverse reactions were chills and fever, but disappeared immediately after stopping the administration of ALG or ATG.
