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 ganciclovir, the following should be considered:

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

Pregnancy—Use of ganciclovir during pregnancy should be avoided whenever possible since ganciclovir has caused cancer and birth defects in animal studies. The use of birth control is recommended during ganciclovir therapy. Men should use a condom while receiving ganciclovir, and for at least 90 days following treatment. Also, animal studies have shown that ganciclovir causes a decrease in fertility.

Breast-feeding—Breast-feeding should be stopped during treatment with this medicine because ganciclovir may cause serious unwanted effects in nursing babies.

Children—Ganciclovir can cause serious side effects in any patient. Therefore, it is especially important that you discuss with the child's doctor the good that this medicine may do as well as the risks of using it.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of ganciclovir in the elderly with use in other age groups.

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 ganciclovir, it is especially important that your health care professional know if you are taking any of the following:

• Amphotericin B by injection (e.g., Fungizone) or
• Antineoplastics (cancer medicine) 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
• Interferon (e.g., Intron A, Roferon-A) or
• Mercaptopurine (e.g., Purinethol) or
• Zidovudine (e.g., AZT, Retrovir)—Caution should be used if these medicines and ganciclovir are used together; receiving ganciclovir while you are using these medicines may make anemia and other blood problems worse

• Carmustine (e.g., BiCNU) or
• Cisplatin (e.g., Platinol) or
• Combination pain medicine containing acetaminophen and aspirin (e.g., Excedrin) or other salicylates (with large amounts taken regularly) or
• Cyclosporine (e.g., Sandimmune) or
• Deferoxamine (e.g., Desferal) (with long-term use) or
• Gold salts (medicine for arthritis) or
• Inflammation or pain medicine, except narcotics, or
• Lithium (e.g., Lithane) or
• Other anti-infectives (e.g., amphotericin B) or
• Penicillamine (e.g., Cupramine) or
• Streptozocin (e.g., Zanosar) or
• Tiopronin (e.g., Thiola)—Use of these medicines may increase the chance of side effects affecting the kidneys

• Methotrexate (e.g., Mexate) or
• Plicamycin (e.g., Mithracin)—These medicines may increase the chance of side effects affecting the blood and the kidneys

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

• Kidney disease—Ganciclovir may build up in the blood in patients with kidney disease, increasing the chance of side effects

• Low platelet count or
• Low white blood cell count—Ganciclovir may make these blood diseases worse