Common brand names

• Cytosar-U

How it is administered

Cytarabine is given as an injection. It can be administered intravenously (IV), subcutaneously (under the skin), or intrathecally (into the spinal fluid, using preservative-free preparations only). The specific method and schedule depend on the treatment plan and the type of leukemia being treated. For most blood cancers, cytarabine is used in combination with other chemotherapy drugs and is given in cycles, often as a continuous infusion or as divided doses over several days.

How it works

Cytarabine is a type of chemotherapy called an antimetabolite. It works by interfering with the DNA of cancer cells, preventing them from growing and dividing. Specifically, cytarabine is most effective against cells that are actively dividing (during the S-phase of the cell cycle). It inhibits an enzyme called DNA polymerase, which is essential for DNA replication. This action leads to cell death, particularly in rapidly growing cancer cells such as those found in leukemia and lymphoma.

Cytarabine can also suppress the immune system by reducing the production of white blood cells, which is why patients receiving this medication need close monitoring. Because it targets dividing cells, it can also affect normal cells that divide quickly, such as those in the bone marrow, digestive tract, and hair follicles, leading to some of its side effects.

Who should take it

Cytarabine is indicated for adults and children as part of combination chemotherapy for the treatment of acute non-lymphocytic leukemia (a group that includes acute myeloid leukemia). It is also used in the treatment of acute lymphocytic leukemia and the blast phase of chronic myelocytic leukemia. Additionally, cytarabine can be administered intrathecally for the prevention and treatment of leukemia involving the central nervous system (meningeal leukemia).

For blood cancers, cytarabine is often used as part of an induction regimen to achieve remission, and may also be used in consolidation or maintenance phases of therapy. The decision to use cytarabine depends on the specific type of leukemia or lymphoma, the patient’s overall health, and other factors determined by the treating physician.

Who should not take it

Cytarabine should not be used in patients who have a known hypersensitivity or allergy to cytarabine or any of its components. It should be used with caution in patients with pre-existing bone marrow suppression, as it can further decrease blood cell counts and increase the risk of infection and bleeding.

Patients with severe liver or kidney impairment may require dose adjustments or may not be suitable candidates for cytarabine, as the drug is metabolized and excreted through these organs. Pregnant women should avoid cytarabine unless the potential benefits outweigh the risks, as it can cause harm to the developing fetus. Breastfeeding is not recommended during treatment due to the potential for serious adverse reactions in nursing infants.

Commonly used with

Cytarabine is most often used in combination with other chemotherapy agents. Common combinations include daunorubicin, idarubicin, or other anthracyclines, especially in induction regimens for acute myeloid leukemia. It may also be used with drugs such as cyclophosphamide, vincristine, prednisone, methotrexate, and asparaginase, depending on the specific type of leukemia or lymphoma being treated.

For central nervous system involvement, cytarabine may be given intrathecally along with methotrexate and hydrocortisone.

Commonly tested with

Cytarabine is frequently tested in combination with other chemotherapy agents in clinical trials for blood cancers. These combinations may include anthracyclines (such as daunorubicin or idarubicin), etoposide, and other agents used in multi-drug regimens for leukemia and lymphoma. It is also tested with supportive care medications to manage side effects and prevent infections during periods of low blood counts.