Cytarabine
Say it: sye-TARE-uh-been
Cytarabine is a chemotherapy medicine that blocks leukemia cells from making the DNA they need to grow.
What it is
Cytarabine looks like one of the building blocks of DNA. Leukemia cells take it in and use it by mistake. This stops them from making new DNA, and they die.
Often used for
- acute myeloid leukemia (AML)
- acute lymphoblastic leukemia (ALL)
- leukemia in the brain and spinal fluid
- and some lymphomas
How you get it
Cytarabine is often given through a vein (IV) as a nonstop drip for several days in the hospital, or in higher doses over a few hours twice a day. It can also be given as a shot under the skin or into the spinal fluid. Your schedule may be different.
Common side effects and what helps
- Very low blood counts, which raise your risk of infection and bleeding. Wash your hands often.
- Nausea and vomiting. Take your anti-nausea medicine as your team tells you.
- Mouth sores. Use a soft toothbrush and gentle rinses.
- Diarrhea. Drink fluids and tell your team if it is frequent.
- Fever, muscle aches, bone pain, and rash a few hours after a dose. Tell your nurse.
- Red, sore eyes with high doses. Use the eye drops your team gives you.
- Feeling tired. Rest when you need to.
Call your care team right away if you have
- A fever of 100.4 degrees Fahrenheit (38 degrees Celsius) or higher, or chills
- Trouble walking, poor balance, slurred speech, or messy handwriting
- Bleeding or bruising that will not stop, black or bloody stools, or blood in your urine
- Shortness of breath
- Eye pain or blurry vision
- Yellow skin or eyes
Before you start, tell your team
- If you are pregnant, may become pregnant, or are breastfeeding
- If you have kidney or liver problems
- If you have had nerve or balance problems
- All the medicines, vitamins, and herbal products you take
Good to know
- High doses can affect the part of the brain that controls balance. Your nurses will check your balance, speech, and handwriting.
- You will get steroid eye drops with high doses to protect your eyes.
- You will have blood tests often to check your blood counts and liver.
- Blood counts can stay low for weeks. You may need transfusions.
At home
- If you give yourself shots under the skin at home, your nurse will teach you how. Use a sharps container for needles.
- If you miss a dose, ask your team what to do.
- Caregivers should wear gloves when handling the medicine and wash hands after.
Questions to ask
- How long will I be in the hospital?
- How long will my blood counts stay low?
- What should my family watch for with high doses?
- Will I need blood or platelet transfusions?
Part of these treatment plans
Side effect guides
- Fatigue (tiredness)
- Nausea and vomiting
- Diarrhea
- Mouth sores
- Low white blood cells and infection risk
- Low platelets and bleeding
- Skin rash (including EGFR-inhibitor rash)
- Pain
Sources
Quick answers
- What is Cytarabine?
- Cytarabine is a chemotherapy medicine that blocks leukemia cells from making the DNA they need to grow.
- What is Cytarabine used for?
- acute myeloid leukemia (AML); acute lymphoblastic leukemia (ALL); leukemia in the brain and spinal fluid; and some lymphomas.
- How is Cytarabine given?
- Cytarabine is often given through a vein (IV) as a nonstop drip for several days in the hospital, or in higher doses over a few hours twice a day. It can also be given as a shot under the skin or into the spinal fluid. Your schedule may be different.
- What are the common side effects of Cytarabine?
- Very low blood counts, which raise your risk of infection and bleeding. Nausea and vomiting. Mouth sores. Diarrhea. Fever, muscle aches, bone pain, and rash a few hours after a dose. Red, sore eyes with high doses. Feeling tired.
- When should I call my care team while taking Cytarabine?
- A fever of 100.4 degrees Fahrenheit (38 degrees Celsius) or higher, or chills; Trouble walking, poor balance, slurred speech, or messy handwriting; Bleeding or bruising that will not stop, black or bloody stools, or blood in your urine; Shortness of breath; Eye pain or blurry vision; Yellow skin or eyes.
- Which chemotherapy plans include Cytarabine?
- 7+3, BEAM, C10403 (CALGB 10403), CLAG-M, FLAG-IDA, HiDAC, Hyper-CVAD, R-DHAP.
Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.