Before Using 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 temozolomide, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to dacarbazine or temozolomide. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—There is a chance that this medicine may cause birth defects if it is taken at the time of conception or if it is taken during pregnancy. You should wait for 6 months after the treatment is finished before becoming pregnant. Studies in rats and rabbits have shown that temozolomide causes birth defects in the fetus and other problems (including miscarriages).

Be sure that you have discussed these possible effects with your doctor before taking this medicine. Before taking temozolomide, make sure your doctor knows if you are pregnant or if you may become pregnant. It is best to use some kind of birth control while you are taking temozolomide. Tell your doctor right away if you think you have become pregnant while taking temozolomide.

If you are a man taking temozolomide you should be very careful not to father a child up to 6 months after treatment. Use a good form of birth control. Treatment with temozolomide may make you sterile. You may want to save and freeze your sperm before you start treatment with temozolomide in case this happens.

Breast-feeding—It is not known whether temozolomide passes into human breast milk. However, temozolomide is not recommended during breast-feeding because it may cause unwanted effects in nursing babies.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing the use of temozolomide in children with use in other age groups.

Older adults—Elderly patients may be more sensitive to the effects of temozolomide. Blood problems such as low platelet (the cell that helps blood to clot) counts and low white blood cell (the cell that helps fight off infections) counts may be especially likely to occur in patients 70 years of age or older.

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 temozolomide it is especially important that your health care professional knows if you are taking any of the following:

• Acyclovir (e.g., Zovirax) or
• Anticonvulsants (seizure medicine) or
• Antidiabetics, oral (diabetes medicine taken by mouth) or
• Anti-infectives by mouth or by injection (medicine for infection) or
• Antipsychotics (medicine for mental illness) or
• Captopril (e.g., Capoten) or
• Enalapril (e.g., Vasotec) or
• Flecainide (e.g., Tambocor) or
• Imipenem or
• Inflammation or pain medicine, except narcotics or
• Lisinopril (e.g., Prinivil, Zestril) or
• Maprotiline (e.g., Ludiomil) or
• Penicillamine (e.g., Cuprimine) or
• Pimozide (e.g., Orap) or
• Procainamide (e.g., Pronestyl) or
• Promethazine (e.g., Phenergan) or
• Ramipril (e.g., Altace) or
• Sulfasalazine (e.g., Azulfidine) or
• Tiopronin (e.g., Thiola) or
• Tocainide (e.g., Tonocard) or
• Tricyclic antidepressants (medicine for depression) or
• Trimeprazine (e.g., Temaril)—Concurrent use of these agents with temozolomide may cause blood disorders
• Alpha Interferons (e.g., Intron A, Roferon-A) or
• Amphotericin B by injection (e.g., Fungizone) or
• Antineoplastics, other (cancer medicine) or
• Antithyroid agents (medicine for overactive thyroid) or
• Azathioprine (e.g., Imuran) or
• Chloramphenicol (e.g., Chloromycetin) or
• Colchicine or
• Flucytosine (e.g., Ancoban) or
• Ganciclovir (e.g., Cytovene) or
• Zidovudine (e.g., AZT, Retrovir)—Concurrent use of these agents with temozolomide increases the risk of infection
• If you have ever been treated with radiation or cancer medicines—Temozolomide may increase the effects that these medicines or radiation therapy may have on the blood

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

• Bone marrow depression, existing or
• Infection—There may be an increased risk of infections or worsening infections because of the body's reduced ability to fight them

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

• Kidney disease or
• Liver disease— Temozolomide should be used with caution