A drug used to treat certain types of leukemia and prevent the spread of leukemia to the meninges (three thin layers of tissue that cover and protect the brain and spinal cord). It is also being studied in the treatment of other types of cancer. Cytarabine blocks tumor growth by stopping DNA synthesis. It is a type of antimetabolite.

A pyrimidine nucleoside analog that is used mainly in the treatment of leukemia, especially acute non-lymphoblastic leukemia. Cytarabine is an antimetabolite antineoplastic agent that inhibits the synthesis of DNA. Its actions are specific for the S phase of the cell cycle. It also has antiviral and immunosuppressant properties. (From Martindale, The Extra Pharmacopoeia, 30th ed, p472)

An antimetabolite analogue of cytidine with a modified sugar moiety (arabinose instead of ribose). Cytarabine is converted to the triphosphate form within the cell and then competes with cytidine for incorporation into DNA. Because the arabinose sugar sterically hinders the rotation of the molecule within DNA, DNA replication ceases, specifically during the S phase of the cell cycle. This agent also inhibits DNA polymerase, resulting in a decrease in DNA replication and repair. (NCI04)

(cytosine arabinoside) Class of pyrimidine nucleoside analogs used mainly in the treatment of leukemia, especially acute non-lymphoblastic leukemia; antimetabolite antineoplastic agents that inhibit the synthesis of DNA with actions specific for the S phase of the cell cycle; also have antiviral and immunosuppressant properties.