• If you are allergic to anything, including medicines, dyes, additives, or foods.

• If you have any medical conditions such as kidney disease, liver disease (including hepatitis), heart disease, congestive heart failure, diabetes, gout, infections, or if you have had kidney stones. These conditions may require that your medicine dose, regimen, or timing be changed.

• If you are pregnant, trying to get pregnant, or if there is any chance of pregnancy. This drug may cause birth defects if either the male or female is taking it at the time of conception or during pregnancy. If you are sexually active and taking this drug, you should use some kind of birth control. It is important to check with your doctor about what kinds of birth control can be used with this medicine.

• If you are breastfeeding. It is not known whether this drug passes into breast milk. If it does, it could harm the baby.

• If you think you might want to have children in the future. Some drugs can cause sterility. Talk with your doctor about the possible risk with this drug and the options that may preserve your ability to have children.

• If you have been treated previously for cancer with radiation or chemotherapy as these may influence how much of these treatments you can have again.

• About any other prescription or over-the-counter medicines you are taking, including vitamins and herbs.

Your doctor will likely test your blood throughout your treatment, looking for possible effects of the drug on blood counts (described below) or on other body organs. Based on the test results, you may be given medicines to help treat any effects. Your doctor may also need to reduce or delay your next dose of this drug, or even stop it altogether.

This drug can lower your white blood cell count, especially in the weeks after the drug is given. This can increase your chance of getting an infection. Be sure to let your doctor or nurse know right away if you have any signs of infection, such as fever (100.5° or higher), chills, pain when passing urine, a new cough, or bringing up sputum.

Fludarabine may lower your platelet count in the weeks after it is given, which can increase your risk of bleeding. Speak with your doctor before taking any drugs or supplements that might affect your body's ability to stop bleeding, such as aspirin or aspirin-containing medicines, warfarin (Coumadin), or vitamin E. Tell your doctor right away if you have unusual bruising, or bleeding such as nosebleeds, bleeding gums when you brush your teeth, or black, tarry stools.

Do not get any immunizations (vaccinations), either during or after treatment with this drug, without your doctor's OK. This drug may affect your immune system, which could make vaccinations ineffective, or could even lead to serious infections. Try to avoid contact with people who have recently received a live virus vaccine, such as the oral polio vaccine or smallpox vaccine. Check with your doctor about this.

If you notice tingling of your hands or feet, confusion, problems with your vision, or clumsiness (poor coordination), contact your doctor right away. These symptoms may appear a few weeks or even a couple of months after treatment.

• decreased white blood cell count with increased risk of infection*
• decreased platelet count with increased risk of bleeding*
• low red blood cell count (anemia) with tiredness and weakness
• tiredness (fatigue)
• nausea
• vomiting

• pneumonia
• diarrhea

• numbness and tingling in hands and/or feet related to irritation of nerves*
• changes in vision*
• agitation
• confusion*
• clumsiness*
• cough
• difficulty breathing
• weakness

*See "Precautions" section for more detailed information.