SIDE EFFECTS: 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. As your immune system gets stronger, it can begin to fight off infections you already had, possibly causing disease symptoms to come back. You could also have symptoms if your immune system becomes overactive. This reaction may happen at any time (soon after starting HIV treatment or many months later). Get medical help right away if you have any serious symptoms, including: unexplained weight loss, severe tiredness, muscle aches/weakness that doesn't go away, headaches that are severe or don't go away, joint pain, numbness/tingling of the hands/feet/arms/legs, vision changes, signs of infection (such as fever, chills, swollen lymph nodes, 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 trouble breathing/swallowing/moving your eyes, drooping face, paralysis, trouble speaking). Tell your doctor right away 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 right away if any of these rare but very serious side effects occur: seizures. Loss of body fat (such as in the face, arms, legs, and buttocks) may occur while you are taking this medication. This effect may be permanent. Tell your doctor right away if you notice any changes in body fat. 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. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking zidovudine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney problems, liver problems (such as hepatitis B or C, cirrhosis), alcohol use, low red/white blood cells. 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. Ask your doctor or pharmacist about using this product safely. 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. Tell your doctor if you are pregnant before using this medication. Treatment can lower the risk of passing HIV infection to your baby. Discuss the risks and benefits with your doctor. This medication passes into breast milk. Because breast milk can transmit HIV, do not breast-feed.

DRUG INTERACTIONS: The effects of some drugs can change if you take other drugs or herbal products at the same time. This can increase your risk for serious side effects or may cause your medications not to work correctly. These drug interactions are possible, but do not always occur. Your doctor or pharmacist can often prevent or manage interactions by changing how you use your medications or by close monitoring. To help your doctor and pharmacist give you the best care, be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products) before starting treatment with this product. While using this product, do not start, stop, or change the dosage of any other medicines you are using without your doctor's approval. Some products that may interact with this drug include: orlistat, 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 methadone, rifampin, and some drugs used to treat seizures (such as phenytoin, valproic acid). This is not a complete list. This medication must not be taken with other medications that contain zidovudine. Check the labels on all your other prescription medications to make sure they do not contain zidovudine. If you have any questions, consult your doctor or pharmacist. This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include extreme drowsiness/tiredness, confusion, seizures.