Zidovudine is an antiviral medicine used to treat HIV, the virus that can cause acquired immunodeficiency syndrome (AIDS). Zidovudine is also given during pregnancy to prevent an HIV-infected woman from passing the virus to her baby. Zidovudine is not a cure for HIV or AIDS.

Zidovudine may also be used for purposes not listed in this medication guide.

You may develop lactic acidosis, a dangerous build-up of lactic acid in your blood. Get emergency medical help if you have unusual muscle pain, trouble breathing, irregular heartbeats, dizziness, vomiting, or if you feel cold, tired, or very weak.

Zidovudine can lower blood cells that help your body fight infections and help circulate oxygen. Zidovudine can also cause severe or life-threatening effects on your liver.

Call your doctor if you have symptoms such as: fever, flu symptoms, unusual tiredness, mouth sores, pale skin, cold hands and feet, upper stomach pain, dark urine, or jaundice (yellowing of the skin or eyes).

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Zidovudine oral is taken by mouth, usually in combination with other antiviral medications.

Zidovudine injection is given as an infusion into a vein. A healthcare provider will give you this injection if you are unable to take the medicine by mouth.

Zidovudine oral can be taken with or without food.

Measure liquid medicine carefully, especially when giving zidovudine to a baby. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

Zidovudine doses are based on weight in children. Your child's dose needs may change if the child gains or loses weight.

Zidovudine can lower blood cells that help your body fight infections and help circulate oxygen in your body. You may get an infection or feel more tired than usual. Your blood will need to be tested often.

Use all HIV medications as directed and read all medication guides you receive. Do not change your dose or dosing schedule without your doctor's advice. Every person with HIV should remain under the care of a doctor.

Store zidovudine oral at room temperature away from moisture and heat.

You should not use zidovudine if you are allergic to it.

You may develop lactic acidosis, a dangerous build-up of lactic acid in your blood. This may be more likely if you have other medical conditions, if you've taken HIV medication for a long time, or if you are a woman. Ask your doctor about your risk.

Zidovudine can also cause severe or life-threatening effects on your liver. Tell your doctor if you have liver disease, especially hepatitis C.

Tell your doctor if you have ever had:

• kidney disease;

• muscle problems;

• a latex allergy (if you receive zidovudine injection);

• bone marrow suppression;

• anemia (low red blood cells); or

• if you drink large amounts of alcohol.

Tell your doctor if you are pregnant, and use your medications properly to control your infection. HIV can be passed to your baby if the virus is not controlled during pregnancy. Your name may be listed on a registry to track any effects of antiviral medicine on the baby.

Women with HIV or AIDS should not breast feed a baby. Even if your baby is born without HIV, the virus may be passed to the baby in your breast milk.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Because you will receive zidovudine injection in a clinical setting, you are not likely to miss a dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Avoid drinking alcohol. It may increase your risk of liver damage or lactic acidosis.

Using zidovudine will not prevent your disease from spreading. Do not have unprotected sex or share razors or toothbrushes. Talk with your doctor about safe ways to prevent HIV transmission during sex. Sharing drug or medicine needles is never safe, even for a healthy person.

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).

Mild symptoms of lactic acidosis may worsen over time, and this condition can be fatal. Get emergency medical help if you have: unusual muscle pain, trouble breathing, stomach pain, vomiting, irregular heart rate, dizziness, feeling cold, or feeling very weak or tired.

Zidovudine may cause serious side effects. Call your doctor at once if you have:

• low blood cell counts--fever, chills, tiredness, mouth sores, skin sores, easy bruising, unusual bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath; or

• liver problems--swelling around your midsection, right-sided upper stomach pain, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Zidovudine affects your immune system, which may cause certain side effects (even weeks or months after you've used zidovudine). Tell your doctor if you have:

• signs of a new infection--fever, night sweats, swollen glands, cold sores, cough, wheezing, diarrhea, weight loss;

• trouble speaking or swallowing, problems with balance or eye movement, weakness or prickly feeling; or

• swelling in your neck or throat (enlarged thyroid), menstrual changes, impotence.

Common side effects of zidovudine may include:

• headache;

• fever, general ill feeling;

• cough;

• nausea, vomiting, loss of appetite; or

• loss of body fat (especially in your arms, legs, face, and buttocks).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your doctor about all your other medicines, especially:

• doxorubicin;

• ribavirin;

• stavudine; or

• other medicines that contains zidovudine (including combination drugs such as Combivir or Trizivir).

This list is not complete. Other drugs may affect zidovudine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.