Abacavir

What it is used for

Abacavir tablets, in combination with other antiretroviral agents, are indicated for the treatment of human immunodeficiency virus (HIV-1) infection.

How it is taken

Before starting abacavir, you must be tested for the HLA-B*5701 allele. For adults, the usual dose is 600 mg daily, taken as either 300 mg twice daily or 600 mg once daily. For children aged 3 months and older, the dose is based on body weight and should not exceed 600 mg daily. For patients with mild liver problems (Child-Pugh Class A), the recommended dose is 200 mg twice daily.

Warnings

• Serious and sometimes fatal hypersensitivity reactions can occur with abacavir. Symptoms may include fever, rash, nausea, vomiting, diarrhea, abdominal pain, fatigue, achiness, cough, or sore throat.
• Patients who carry the HLA-B*5701 allele are at higher risk for hypersensitivity reactions.
• Abacavir is contraindicated in patients with a prior hypersensitivity reaction to abacavir and in HLA-B*5701-positive patients.
• If a hypersensitivity reaction is suspected, stop abacavir immediately and never restart it or any other abacavir-containing product.
• Lactic acidosis and severe liver problems (hepatomegaly with steatosis) have been reported.
• Immune reconstitution syndrome and myocardial infarction have been reported.

Common side effects

• Nausea
• Headache
• Malaise and fatigue
• Nausea and vomiting
• Dreams/sleep disorders
• Fever and/or chills (in children)
• Skin rashes (in children)
• Ear/nose/throat infections (in children)

Interactions

Abacavir may interact with methadone (an increased methadone dose may be needed in a small number of patients) and riociguat (the riociguat dose may need to be reduced).