Zidovudine injection is used along with other medications to treat human immunodeficiency virus (HIV) infection. Zidovudine is given to HIV-positive pregnant women to reduce the chance of passing the infection to the baby. Zidovudine injection is in a class of medications called nucleoside reverse transcriptase inhibitors (NRTIs). It works by decreasing the amount of HIV in the blood. Although zidovudine injection does not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses such as serious infections or cancer. Using or taking these medications along with practicing safer sex and making other life-style changes may decrease the risk of transmitting (spreading) the HIV virus to other people.

Zidovudine injection may decrease the number of certain cells in your blood, including red and white blood cells. Tell your doctor if you have or have ever had a low number of any type of blood cells or any blood disorders such as anemia (a lower than normal number of red blood cells) or bone marrow problems. Call your doctor immediately if you experience any of the following symptoms: unusual bleeding or bruising, fever, chills, or other symptoms of infection, unusual tiredness or weakness, or pale skin.

Zidovudine injection also may cause life-threatening damage to the liver and a potentially life-threatening condition called lactic acidosis (buildup of lactic acid in the blood). Tell your doctor if you have or have ever had liver disease. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment: nausea, vomiting, pain in the upper right part of your stomach, loss of appetite, extreme tiredness, weakness, dizziness, lightheadedness, fast or irregular heartbeat, trouble breathing, dark yellow or brown urine, light-colored bowel movements, yellowing of the skin or eyes, feeling cold, especially in the arms or legs, or muscle pain that is different than any muscle pain you usually experience.

Zidovudine injection may cause muscle disease, especially when used for a longer period of time. Call your doctor if you experience tiredness, muscle pain, or weakness.

It is important to keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to zidovudine injection.

Talk to your doctor about the risks of receiving zidovudine injection.

Zidovudine injection comes as a solution (liquid) to inject intravenously (into a vein). It is usually given over an hour every 4 hours, but infants 6 weeks of age and younger may receive it over a period of 30 minutes every 6 hours. During labor and delivery, women may receive a continuous zidovudine infusion until the baby is delivered.

Your doctor may temporarily stop your treatment if you experience serious side effects.

You may receive zidovudine injection in a hospital, or you may administer the medication at home. If you will be receiving zidovudine injection at home, your healthcare provider will show you how to use the medication. Be sure that you understand these directions, and ask your healthcare provider if you have any questions.

Before using zidovudine injection,

• tell your doctor and pharmacist if you are allergic to zidovudine, any other medications, latex, or any of the other ingredients in zidovudine injection. Ask your pharmacist for a list of the ingredients. If you will be giving the infusion, tell your doctor if you or the person who will be injecting the medication for you if you are allergic to rubber or latex.
• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, you are taking or plan to take. Be sure to mention any of the following: certain chemotherapy medications for cancer such as doxorubicin (Doxil); ganciclovir (Cytovene, Valcyte); interferon alfa, ribavirin (Copegus, Rebetol, Ribasphere); and stavudine (Zerit). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you have or have ever had kidney disease.
• tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while receiving zidovudine injection, call your doctor. You should not breastfeed if you are infected with HIV or if you are using zidovudine injection.
• you should know that you may have a loss of body fat from your face, legs, and arms. Talk to your doctor if you notice this change.
• you should know that while you are using medications to treat HIV infection, your immune system may get stronger and begin to fight other infections that were already in your body. This may cause you to develop symptoms of those infections. If you have new or worsening symptoms after starting treatment with zidovudine injection, be sure to tell your doctor.

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

• fatigue
• headache
• vomiting

Unless your doctor tells you otherwise, continue your normal diet.

Zidovudine injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• headache
• nausea
• vomiting
• constipation
• diarrhea (especially in children)
• stomach cramps or pain
• difficulty falling asleep or staying asleep
• heartburn

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:

• rash
• blistering or peeling of the skin
• hives
• itching
• difficulty breathing or swallowing
• swelling of the eyes, face, tongue, lips, or throat

Zidovudine injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.