zerit and Azt Interactions

Interactions between zerit(stavudine) and Azt (zidovudine)

zidovudine and stavudine (Moderate Drug-Drug)

GENERALLY AVOID: In vitro data have demonstrated an antagonistic relationship between zidovudine and stavudine. The proposed mechanism is competition for phosphorylating enzymes required for nucleoside activation. A 41% reduction in active stavudine metabolites was reported when zidovudine was administered with stavudine. No effect on zidovudine activity was noted. Reduced stavudine activation and loss of antiviral activity due to prior zidovudine modification of intracellular phosphorylation has been suggested, but this was not confirmed by other studies. Further clarification is needed.

MANAGEMENT: The manufacturer recommends against concurrent use.