Abacavir

Warning

In some patients, abacavir has caused a serious (sometimes fatal) allergic reaction. Your doctor should order a blood test to measure your risk before you start this medication or take it again. If the blood test shows you are at greater risk, you should not take this medication and your doctor should discuss other treatment choices with you. Symptoms of an allergic reaction may include any of the following: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing, fever, extreme tiredness, nausea, vomiting, diarrhea, stomach pain, muscle aches, sore throat, or cough. Get medical help right away if you experience any of these symptoms. If you have stopped taking abacavir because of an allergic reaction, you must never take any form of abacavir again, or death could result. Tell all of your doctors and pharmacists if you have stopped taking abacavir due to an allergic reaction. Also, properly throw away any unused abacavir. Read the warning card provided with this medication for more details.

Precautions

See also Warning and How to Use sections.

Before taking abacavir, 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: liver problems (such as hepatitis B or C, or cirrhosis), kidney problems, alcohol use.

Abacavir may increase your risk of a heart attack. Discuss the risks and benefits of treatment with your doctor and ways to lower your risk of heart disease. Tell your doctor if you have heart problems, if you smoke, or if you have other conditions that increase your risk of heart disease such as high blood pressure, diabetes, or high cholesterol levels.

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

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 may transmit HIV, consult your doctor before breastfeeding.

Side Effects

See also Warning and How to Use sections.

Trouble sleeping or loss of appetite may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor 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 unsteadiness, loss of coordination, trouble swallowing/speaking/chewing, trouble moving your eyes).

Tell your doctor right away if you have any serious side effects, including: mental/mood changes (depression, anxiety).

Rarely, this medication has caused severe (sometimes fatal) liver problems and a buildup of lactic acid in the blood (lactic acidosis). These serious side effects may occur more often in women and obese patients. Get medical help right away if you have any of the following serious symptoms, including: symptoms of liver problems (such as nausea/vomiting that doesn't stop, stomach/abdominal pain, yellowing eyes/skin, dark urine), symptoms of lactic acidosis (such as deep/rapid breathing, drowsiness, nausea/vomiting).

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.

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