Arabinosylcytosine, Cytarabine

Diagram of the molecular structure of Arabinosylcytosine, Cytarabine
Brand name: Cytosar®
Brand name: ara-C
IUPAC: 4-amino-1-[(2R,3S,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]pyrimidin-2-one
FDA approval: Yes

Malignancies for which cytarabine is used include: Acute non-lymphocytic leukemia, Acute lymphocytic leukemia and Chronic myelocytic leukemia. Cytarabine (Cytosar®, ara-C) is administered as an infusion or as in injection under the skin.


Cytarabine (Cytosar®, ara-C) is an antimetabolite that acts as a pyrimidine antagonist. It is thought that its primary activity is interrupting DNA synthesis.

The molecular structure above shows Arabinosylcytosine, Cytarabine.

Side effects:

Common side effects include: bone marrow suppression, anorexia, nausea and vomiting, diarrhea, oral/anal inflammation or ulceration, rash, fever. Cytarabine (Cytosar®, ara-C) is a suppressor of bone marrow activity. It is important to monitor blood cell and platelet counts throughout the duration of treatment with blood tests done often. 1

  • 1Cytosar. Product Monograph. Pfizer. September, 2014. []

Cytarabine should not be taken by women who are pregnant and patients should not become pregnant while using this drug, as it may have harmful affects on the developing fetus. 1

  • 1Cytosar. Product Monograph. Pfizer. September, 2014. []