Presence of HLA-B*5701 allele. Prior hypersensitivity reaction to any of the components (see full labeling). Moderate or severe hepatic impairment.
Screen for presence of HLA-B*5701 allele prior to starting therapy or reinitiation; if (+), abacavir is contraindicated. Discontinue immediately if hypersensitivity is suspected, regardless of HLA-B*5701 status and even when other diagnoses are possible. If hypersensitivity cannot be ruled out, do not restart. If stopped for reasons other than hypersensitivity, restart only if medical care can be readily accessed. Bone marrow suppression; monitor CBCs esp. in advanced HIV-1 disease. Myopathy with prolonged zidovudine use. Suspend if lactic acidosis or hepatotoxicity (eg, hepatomegaly and steatosis) occurs. Not for treating hepatitis B; monitor patients co-infected with HBV for at least several months after stopping treatment (discontinuing may exacerbate HBV infection). Coronary heart disease. Diabetes. Smoking. Women, obesity, prolonged nucleoside exposure: increased risk of toxicity. Renal impairment (CrCl <50mL/min): not recommended. Mild hepatic impairment: use individual components if dose reductions are required. Elderly. Pregnancy. Nursing mothers: not recommended.
Concomitant stavudine, doxorubicin, ribavirin: not recommended. Abacavir may antagonize methadone. TMP/SMX, nelfinavir may potentiate lamivudine. Ethanol may potentiate abacavir. Atovaquone, fluconazole, methadone, nelfinavir, probenecid, rifampin, ritonavir, valproic acid may affect zidovudine levels; monitor. Increased hematologic toxicity with ganciclovir, other bone marrow suppressants or cytotoxic agents. Monitor for treatment-associated toxicities (esp. hepatic decompensation) with interferon-alpha with or without ribavirin.