Clolar treats a certain type of blood cancer. Drink plenty of fluids every day during your treatment. It can lower your blood count and can increase the risk for an infection. Report a fever.

Clolar Overview


Clolar is a prescription medication used to treat acute lymphoblastic leukemia, or ALL. Clolar belongs to a group of drugs called purine nucleoside antimetabolites. These work by killing existing cancer cells and limiting the development of new cancer cells.

This medication is available in an injectable form to be given directly into a vein (IV) by a healthcare professional.

Common side effects include nausea, vomiting, and diarrhea.

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Clolar Cautionary Labels


Uses of Clolar

Clolar is used to treat acute lymphoblastic leukemia, or ALL. ALL is a type of cancer of the white blood cells. Clolar is used in children and young adults 1 to 21 years old who have already received at least two other treatments.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.


Clolar Drug Class

Clolar is part of the drug class:

Side Effects of Clolar

Common side effects include the following:

  • nausea
  • vomiting
  • diarrhea
  • febrile neutropenia - a low white blood cell count accompanied by a fever
  • headache
  • rash
  • itching
  • fever
  • fatigue
  • reddening, swelling, numbness and sloughing of skin on the palms and soles of the feet
  • anxiety
  • flushing
  • inflammation of the mucosal membranes (such as in the mouse, nose, and throat)

This is not a complete list of this medication’s side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Clolar Interactions

No Clolar drug interactions have been identified. However, you should tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Not all drug interactions are known or reported and new drug interactions are continually being reported.


Clolar Precautions

Serious side effects have been reported with Clolar including the following:

  • Hematologic (blood) toxicity. Return for regular blood counts and report any symptoms associated with hematologic (blood ) toxicity such as weakness, fatigue, pallor, shortness of breath, easy bruising, petechiae, purpura, fever to your doctor.
  • Infection. Report any signs or symptoms of infection (such as a fever, cough, or runny nose) to your doctor right away.
  • A decline in liver function. Tell your healthcare provider about any signs or symptoms of liver damage, which include the following:
    • loss of appetite or start losing weight (anorexia)
    • nausea or vomiting
    • feel tired
    • stomach pain or tenderness
    • dark urine or light colored stools
    • yellowing of your skin or the whites of your eyes
    • fever or rash
  • A decline in kidney function. Toxicity from Clolar may occur with kidney dysfunction. Your doctor may want to monitor your kidney functions with certain blood tests as well. Tell your healthcare provider right away right away if you have any of the following symptoms of kidney dysfunction:
    • swelling of face, ankles, hands, or feet
    • fatigue
    • paleness of skin
    • decreased urination
    • shortness of breath
    • change in blood pressures
  • Systemic Inflammatory Response Syndrome (SIRS)/Capillary Leak Syndrome. Signs or symptoms of SIRS include fever, a racing heart beat, difficulty, and low blood pressure.
  • Pregnancy and Breastfeeding. It is advisable to use effective contraceptive measures to prevent pregnancy. Avoid breastfeeding during treatment.
  • Gastrointestinal Disorders. You may experience nausea, vomiting, and/or diarrhea. If these symptoms are severe, you should seek medical attention.
  • Rash. You may experience skin rash Clolar. If this symptom is severe, seek medical attention.

Do not take this medication if you are allergic to Clolar or to any of its ingredients.

Clolar Food Interactions

Drink plenty of fluids every day during your treatment with Clolar, especially if you vomit or have diarrhea.

Inform MD

Before using Clolar,

  • tell your doctor and pharmacist if you are allergic to Clolar or any other medications
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention medications for high blood pressure and heart disease. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had kidney or liver disease
  • tell your doctor if you are pregnant or plan to become pregnant. Clolar may harm the fetus. You should use birth control to prevent pregnancy during your treatment with Clolar. Talk to your doctor about types of birth control that will work for you. If you become pregnant while using Clolar, call your doctor.
  • tell your doctor if you are breastfeeding. You should not breastfeed during your treatment with Clolar.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are receiving Clolar.
  • you should know that clofarabine may cause a skin condition called hand-foot syndrome. If you develop this condition, you may experience tingling of the hands and feet, and then reddening, dryness, and flaking of the skin on the hands and feet. If this happens, ask your doctor to recommend a lotion that you can apply to these areas. You will need to apply the lotion lightly and avoid rubbing the areas forcefully. Your doctor may also prescribe medication to relieve these symptoms.


Clolar and Pregnancy

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

This medication falls into category D. In animal studies, pregnant animals were given this medication and had some babies born with problems. No well-controlled studies have been done in humans. It is advisable to use effective contraceptive measures to prevent pregnancy.

Clolar and Lactation

Tell your doctor if you are breastfeeding or plan to breastfeed.

It is not known if Clolar crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. It is advisable to avoid breastfeeding while taking Clolar.


Clolar Usage

This medication is available in an injectable form to be given directly into a vein (IV) by a healthcare professional.

Clolar Dosage

This medication is available in an injectable form to be dosed by a healthcare professional.

The recommended dose of 52 mg/m2 as an intravenous (into the vein) infusion over 2 hours daily for 5 days in a row.

Cycles are repeated following recovery or return to baseline function (approximately every 2 to 6 weeks). The dosage is based on body surface area (BSA).

Clolar Overdose

If this medication is administered by a healthcare provider in a medical setting, it is unlikely that an overdose will occur. However, if overdose is suspected, seek emergency medical attention.