• 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 have previously been treated with radiation or chemotherapy. Your doctor may want to give you lower doses of dacarbazine.

• 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. Men and women who are taking this drug need to 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 breast-feeding. 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.

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

Dactinomycin may also be used to treat a local area of cancer by infusing it into the artery that supplies the cancerous area with blood. The side effects depend on how much of the drug is absorbed into the body.

Dactinomycin is very toxic. If it is given at home, it must be handled very carefully. Avoid inhaling the powder or liquid, allowing contact with your skin, or getting it near your face. Talk with your doctor or nurse about specific safety instructions.

Your doctor will probably 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.

Dactinomycin 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.

This drug may lower your platelet count in the weeks after it is given, which can increase your risk of bleeding. Talk 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.

Dactinomycin may lower your red blood cell count. If this occurs, it is usually a few months after starting treatment. A low red blood cell count (known as anemia) can cause shortness of breath, or make you to feel weak or tired all the time. Your doctor may give you medicines to help prevent or treat this condition, or you may need to get blood transfusions.

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.

You may have nausea and vomiting on the day you receive this drug or in the first few days afterward. Your doctor may give you medicine before your treatment to help prevent nausea and vomiting. You will probably also get a prescription for an anti-nausea medicine that you can take at home. It is important to have these medicines on hand and to take them as prescribed by your doctor.

This drug may cause hair loss. You may want to talk to your doctor or nurse about getting a wig before starting treatment. If your insurance does not cover it, there may be other resources to help you. Hair loss is usually temporary, and your hair will probably grow back during or after treatment.

Dactinomycin can cause radiation recall. When a person receives this drug, the skin or tissue damage from prior radiation therapy can become red and appear damaged again. Tell your doctor or nurse if your skin gets red in areas where radiation was given.

Because of the way this drug acts on cells in the body, it may increase your long-term risk of getting a second type of cancer, such as leukemia. This is rare, but if it does occur it would likely be years after the drug is used. If you are getting this drug, your doctor feels this risk is outweighed by the risk of what might happen if you do not get this drug. You may want to discuss these risks with your doctor.

• decreased white blood cell count with increased risk of infection*
• nausea*
• vomiting*
• loss of appetite
• decreased platelet count with increased risk of bleeding*
• sores in mouth or on lips, esophagus, or rectal area (worse if these areas have been recently treated with radiation)
• darkening of skin along vein used for giving the drug
• diarrhea
• rash
• hair loss*
• radiation recall skin changes*

• tiredness (fatigue)
• abdominal pain
• fever
• fetal abnormalities if taken while you are pregnant or if you become pregnant while taking this drug
• muscle and bone aches
• depression

• liver damage
• kidney damage
• second type of cancer*
• severe allergic reaction at the time the drug is given, with dizziness, itching, rash, shortness of breath, or swelling in the face, tongue, or throat.

*See "Precautions" section for more detailed information.