Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Allergic reactions: At the time of receiving this medication, make sure you are given a leaflet and warning card that will help you to recognize the signs and symptoms of allergy to abacavir. Abacavir causes an allergic reaction in approximately 8% of people. The symptoms usually appear within the first 6 weeks of treatment, but may occur at any time during therapy. People who suffer an allergic reaction to abacavir should never take the medication again. Some people are at higher risk of this allergic reaction. Your doctor can perform a blood test to see if you are at greater risk. If you have 2 or more of the following sets of symptoms, you may be experiencing a serious allergic reaction:
- nausea, vomiting, diarrhea, or abdominal pain
- severe tiredness, aches, or general ill feeling
- skin rash
- sore throat, shortness of breath, or coughing
Fat redistribution: Over time, this medication may change how fat is distributed in your body and may change your body shape. You may notice increased fat in the upper back and neck, breast, around the back, chest, and stomach area; or loss of fat from the legs, arms, and face. The long-term effects of this are not known.
Heart attack: The use of abacavir is associated with an increased risk of heart attack. Due to this increased risk, if you have any of the following conditions or risk factors, tell your doctor about them:
- diseases that increase your risk of heart disease, such as high blood pressure and diabetes
- heart problems
Immune reconstitution syndrome: This medication may cause immune reconstitution syndrome, where signs and symptoms of inflammation from previous infections appear. These symptoms occur soon after starting anti-HIV medication and can vary. They are thought to occur as a result of the immune system improving and being able to fight infections that have been present without symptoms (such as pneumonia, herpes, or tuberculosis). Report any new symptoms to your doctor immediately.
Lactic acidosis and enlarged liver: This medication can cause a rare but serious condition called lactic acidosis, together with an enlarged fatty liver. You may be more likely to experience these problems if you are female, obese, have known risk factors for liver disease, or have been taking medications such as abacavir for a long time. If you experience weakness, loss of appetite, sudden unexplained weight loss, abdominal pain, and difficulty breathing or rapid breathing, contact your doctor immediately or seek immediate medical attention.
Liver function: Abacavir is removed from the body by the liver and may cause liver problems. People with moderately-to-severely reduced liver function should not take abacavir. If you have liver disease or decreased liver function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
If you experience symptoms of liver problems (e.g., abdominal pain, persistent vomiting, feeling unwell, fever, itching, yellowing of the skin and eyes, dark urine), contact your doctor immediately.
Stopping the medication: If you stop taking this medication, your HIV infection could get worse. Take the medication exactly as prescribed by your doctor, and do not stop taking the medication without checking with your doctor first.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: This medication may pass into breast milk and affect your baby. Since HIV can be transmitted by breast milk, women who have HIV infection are cautioned against breast-feeding because of the risk of passing HIV to a baby who does not have the infection.
Children: The safety and effectiveness of this medication have not been established for children less than 3 months of age. The safety and effectiveness of once-daily dosing have not been established for adolescents and children less than 18 years of age and should therefore be avoided.
Seniors: Seniors are more likely to have reduced kidney, liver, and heart function, putting them at increased likelihood of experiencing side effects. They may require lower doses. The safety and effectiveness of once-daily doses of abacavir have not been studied for people more than 65 years of age and should therefore be avoided.