Common brand names

• Cytosar-U

How it is administered

Cytarabine is not effective when taken by mouth and must be given by injection. It can be administered in several ways:

• Intravenous (IV) infusion or injection: Directly into a vein, either as a slow infusion over several hours or as a rapid injection.
• Subcutaneous injection: Injected under the skin.
• Intrathecal injection: Injected directly into the fluid around the spinal cord (for certain types of leukemia involving the central nervous system; only preservative-free formulations should be used for this purpose).

The exact schedule and method depend on the treatment plan prescribed by your doctor and the specific blood cancer being treated.

How it works

Cytarabine is a type of chemotherapy medication known as an antimetabolite. It works by interfering with the DNA synthesis of rapidly dividing cells, such as cancer cells. Cytarabine is especially active during the S-phase of the cell cycle, which is when DNA is being copied in preparation for cell division.

Once inside the body, cytarabine is converted into an active form that blocks the action of DNA polymerase, an enzyme necessary for making new DNA. This prevents cancer cells from multiplying and can lead to their death. Because it targets rapidly dividing cells, cytarabine also affects some healthy cells that divide quickly, which can lead to side effects.

Who should take it

Cytarabine is used in combination with other approved anti-cancer drugs to induce remission in adults and children with acute non-lymphocytic leukemia (also called acute myeloid leukemia or AML). It is also used in the treatment of acute lymphocytic leukemia (ALL) and the blast phase of chronic myelocytic leukemia (CML).

Additionally, cytarabine can be administered intrathecally (into the spinal fluid) for the prevention and treatment of meningeal leukemia (leukemia involving the membranes around the brain and spinal cord). The specific use and dosing will be determined by your healthcare provider based on your diagnosis and overall health.

Who should not take it

Cytarabine should not be used by patients who are hypersensitive (allergic) to cytarabine or any of its components.

Cytarabine is a potent bone marrow suppressant, so it should be used with caution in patients who already have significant bone marrow suppression from previous treatments. It should also be used with caution in patients with poor liver or kidney function, as these conditions can increase the risk of toxicity. Women who are pregnant should avoid cytarabine because it can cause harm to the developing fetus. If you are breastfeeding, you should discuss with your doctor whether to discontinue the drug or stop nursing, as it is not known if cytarabine passes into breast milk.

Commonly used with

Cytarabine is most often used in combination with other chemotherapy drugs. For blood cancers like AML, it is commonly combined with medications such as daunorubicin or other anthracyclines. The exact combination depends on the specific type of leukemia and the treatment protocol your doctor recommends.

Commonly tested with

Cytarabine is frequently tested and used in combination with other chemotherapy agents, such as daunorubicin, as part of multi-drug regimens for blood cancers. It may also be used with drugs like cyclophosphamide, vincristine, prednisone, and others, depending on the type of leukemia and the phase of treatment. Your healthcare team will select the most appropriate regimen based on your diagnosis and overall health.