Cytarabine is used alone or with other chemotherapy drugs to treat certain types of leukemia (cancer of the white blood cells), including acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), and chronic myelogenous leukemia (CML). Cytarabine is also used alone or with other chemotherapy drugs to treat meningeal leukemia (cancer in the membrane that covers and protects the spinal cord and brain). Cytarabine is in a class of medications called antimetabolites.