Ziagen (Abacavir Sulfate) - Drug Interactions, Contraindications, Overdosage

DRUG INTERACTIONS

Ethanol: Abacavir has no effect on the pharmacokinetic properties of ethanol. Ethanol decreases the elimination of abacavir causing an increase in overall exposure [see Clinical Pharmacology].

Methadone: The addition of methadone has no clinically significant effect on the pharmacokinetic properties of abacavir. In a study of 11 HIV-1-infected patients receiving methadone-maintenance therapy with 600 mg of ZIAGEN twice daily (twice the currently recommended dose), oral methadone clearance increased [see Clinical Pharmacology]. This alteration will not result in a methadone dose modification in the majority of patients; however, an increased methadone dose may be required in a small number of patients.

OVERDOSAGE

There is no known antidote for ZIAGEN. It is not known whether abacavir can be removed by peritoneal dialysis or hemodialysis.

CONTRAINDICATIONS

ZIAGEN is contraindicated in patients with previously demonstrated hypersensitivity to abacavir or any other component of the products. NEVER restart ZIAGEN or any other abacavir-containing product following a hypersensitivity reaction to abacavir, regardless of HLA-B*5701 status [see Warnings and Precautions (5.1), Adverse Reactions (6)].

ZIAGEN is contraindicated in patients with moderate or severe hepatic impairment.