Before Receiving This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For pegaspargase, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to pegaspargase.

Pregnancy—Pegaspargase has not been studied in pregnant women or animals; however, many cancer medicines may cause sterility that could be permanent. Although sterility has not been reported with pegaspargase, the possibility of this effect in humans should be kept in mind. Cancer medicines may also cause birth defects; therefore, use during pregnancy is not recommended.

Be sure you have discussed this with your doctor before receiving this medicine. It is best to use some kind of birth control while you are receiving pegaspargase. Tell your doctor right away if you think you have become pregnant while receiving pegaspargase.

Breast-feeding—Because pegaspargase may cause serious side effects, breast-feeding is generally not recommended while you are receiving it.

Children—Infants up to 1 year of age—Safety and efficacy have not been established.

Children 1 year of age and older—This medicine has been studied in children 1 year of age and older and has not been shown to cause different side effects or problems than it does in adults. In fact, the side effects of this medicine seem to be less severe in children than in adults.

Older adults—There is no specific information comparing the use of pegaspargase in the elderly with use in other age groups. Safety and efficacy of pegaspargase in the elderly have not been established.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking pegaspargase, it is especially important that your health care professional know if you are taking any of the following:

• Aspirin or
• Dipyridamole (e.g., Persantine) or
• Heparin or
• Inflammation or pain medicine, except narcotics or
• Warfarin (e.g., Coumadin)—Using any of these medicines together with pegaspargase may increase the risk of bleeding

• Amphotericin B by injection (e.g., Fungizone) or
• Antithyroid agents (medicine for overactive thyroid) or
• Azathioprine (e.g., Imuran) or
• Chloramphenicol (e.g., Chloromycetin) or
• Colchicine or
• Cyclophosphamide (e.g., Cytoxan) or
• Flucytosine (e.g., Ancobon) or
• Ganciclovir (e.g., Cytovene) or
• Interferon (e.g., Intron A, Roferon-A) or
• Mercaptopurine (e.g., Purinethol) or
• Methotrexate (e.g., Mexate) or
• Plicamycin (e.g., Mithracin) or
• Zidovudine (e.g., AZT, Retrovir) or
• If you have ever been treated with radiation or cancer medicines—Pegaspargase may increase the effects of these medicines or radiation therapy on the blood

Other medical problems—The presence of other medical problems may affect the use of pegaspargase. Make sure you tell your doctor if you have any other medical problems, especially:

• Anticoagulant therapy (treatment with blood thinners) or
• Bleeding problems—The chance of bleeding may be increased

• Chickenpox (including recent exposure) or
• Herpes zoster (shingles)—Risk of severe disease affecting other parts of the body

• Diabetes mellitus (sugar diabetes)—The chance of side effects may be increased

• Infection—Pegaspargase can decrease your body's ability to fight infection

• Liver disease—Effects of pegaspargase may be increased because of slower removal of this medicine from the body

• Pancreatitis—The chance of side effects may be increased