Description: Zidovudine is an antiviral drug that inhibits the key enzyme reverse transcriptase and blocks the human DNA polymerase and prevents the human immunodeficiecy virus from multiplying in your body.


Absorption: Rapid absorption in the gastrointestinal tract but delayed if taken with food.

Distribution: Crosses the placenta and blood-brain barrier; enters breast milk and semen.

Metabolism: Intracellular; converted to the active antiviral triphosphate. Hepatic; converted to the inactive glucuronide.

Excretion: Urine (as unchanged drug and metabolites); 1 hr (elimination half-life).


This drug is used with other HIV medications to help control HIV infection. It helps to decrease the amount of HIV in your body so your immune system can work better. This lowers your chance of getting HIV complications (such as new infections, cancer) and improves your quality of life.

Zidovudine is used in pregnant women to prevent passing the HIV virus to the unborn baby.

This medication is also used in newborns born to mothers infected with HIV to prevent infection in the newborns.

Other Uses:

This medication may also be used in combination with other HIV medications to reduce the risk of getting HIV infection after contact with the virus. Consult your doctor for more details.


Should not be given to patients who may have life-threatening allergic reaction to this drug and to any of its components.

How to use Zidovudine:


Oral dose- Take 300 mg of this drug by mouth twice a day in combination with other drugs.

Intravenous dose- This dose is administered by the doctor in a hospital setting. The recommended intravenous dose is 1 mg per kg infused at a constant rate over 1 hour every 4 hours. Patients should receive zidovudine injection only until oral therapy can be administered.

  • Zidovudine can be taken with or without food.
  • If a child is taking this medication, tell your doctor if the child has any changes in weight. Zidovudine doses are based on weight in children.
  • HIV/AIDS is usually treated with a combination of drugs. Use all medications as directed by your doctor.
  • Take this medication 2 hours before or after taking clarithromycin. Clarithromycin may prevent your body from fully absorbing zidovudine.

Availability: This is a prescription only drug.

Blood problems: Zidovudine has caused severe blood problems including a decrease in red blood cells (anemia) and white blood cells (neutropenia). Blood problems may require blood transfusions or stopping your medication.

Muscle problems: This medication may also cause muscle problems (myopathy). Seek immediate medical attention if you develop symptoms of myopathy, such as wasting or decrease in muscle size, muscle weakness/pain/tenderness, weight loss.

Liver and blood problem: Rarely, zidovudine has caused a severe (sometimes fatal) liver and blood problem (lactic acidosis). Tell your doctor immediately if you develop symptoms of liver problems, such as persistent nausea, stomach/abdominal pain, dark urine, yellowing eyes/skin; or symptoms of lactic acidosis, such as rapid breathing, drowsiness, muscle aches.

See also Warning section.

Headache, nausea, vomiting, trouble sleeping, or loss of appetite may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Some people may experience worsening of a previous medical condition (such as an old infection) as their immune systems improve, or develop new conditions because their immune systems have become overactive. This reaction may occur at any time (soon after starting HIV treatment or many months later). Tell your doctor right away if you have any serious side effects, including: unexplained weight loss, persistent muscle aches/weakness, joint pain, numbness/tingling of the hands/feet/arms/legs, severe tiredness, vision changes, severe/persistent headaches, signs of infection (such as fever, chills, trouble breathing, cough, non-healing skin sores), signs of an overactive thyroid (such as irritability, nervousness, heat intolerance, fast/pounding/irregular heartbeat, bulging eyes, unusual growth in the neck/thyroid known as a goiter), signs of a certain nerve problem known as Guillain-Barre Syndrome (such as difficulty breathing/swallowing/moving your eyes, drooping face, paralysis, slurred speech).

Tell your doctor immediately if any of these unlikely but serious side effects occur: mental/mood changes (such as depression, anxiety, confusion), easy bruising/bleeding, skin/fingernail color changes.

Tell your doctor immediately if any of these rare but very serious side effects occur: seizures.

Changes in body fat (such as increased fat in the upper back and stomach areas, decreased fat in the arms and legs) may occur while you are taking HIV medication. The cause and long-term effects of these changes are unknown. Discuss the risks and benefits of therapy with your doctor, as well as the possible role of exercise to reduce this side effect.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.



Liquid products may contain sugar. Caution is advised if you have diabetes or any other condition that requires you to limit sugar in your diet.

Before having surgery, tell your doctors or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, caution is advised when using this drug in older adults because they may be more sensitive to the effects of the drug.

  • Allergy: Before taking zidovudine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies.
  • Medical history: Before using this medication, tell your doctor or pharmacist if you had: kidney problems, liver problems (such as hepatitis B or C, cirrhosis), alcohol use, low red/white blood cells.
  • Hematologic toxicity/ bone marrow suppression: This should be used with caution in patients who have bone marrow There have been reports of pancytopenia associated with the use of zidovudine, which was reversible in most instances after discontinuance of the drug. However, significant anemia, in many cases requiring dose adjustment, discontinuation of zidovudine, and/or blood transfusions, has occurred during treatment with zidovudine alone or in combination with other antiretrovirals.
  • Latex: The vial stoppers for zidovudine injection contain natural rubber latex which may cause allergic reactions in latex-sensitive individuals.
  • Myopathy: Myopathy and myositis with pathological changes, similar to that produced by HIV-1 disease, have been associated with prolonged use of zidovudine.
  • Lactic acidosis/ severe hepatomegaly with steatosis: Treatment with zidovudine should be suspended in any patient who develops clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity (which may include hepatomegaly and steatosis even in the absence of marked transaminase elevations).

Pregnancy Risk:  Category C- During pregnancy, this medication should be used only when clearly needed.

Breastfeeding:  This medication passes into breast milk. Because breast milk can transmit HIV, do not breast-feed.


  • Some products that may interact with this drug include: interferon, probenecid, ribavirin, stavudine, drugs that may suppress bone marrow function (such as ganciclovir, dapsone, trimethoprim, chemotherapy including doxorubicin, vincristine), drugs that may affect the kidneys (including NSAIDs such as ibuprofen or naproxen).
  • Other medications can affect the removal of zidovudine from your body, thereby affecting how zidovudine works. These drugs include atovaquone, methadone, rifampin, and some drugs used to treat seizures (such as phenytoin, valproic acid). This is not a complete list.


If overdose is suspected, contact a poison control center or emergency room immediately. Symptoms of overdose may include extreme drowsiness/tiredness, confusion, seizures.


Do not share this medication with others.

Laboratory and/or medical tests (such as blood counts, liver tests, viral load, T-cell counts) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.

Keep all medical and laboratory appointments.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.


Store at room temperature between 59-77 degrees F (15-25 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.


Also marketed as

  • Retrovir [ GlaxoSmithKline ]

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