Indinavir CYP3A4/5/7 substrate

Drug-drug transport interactions are important in combinationtherapy with HIV protease inhibitors (117). Many protease inhibitors are substrates for and inhibitors of CYP3A4 and P-gp. Different combination effects (e.g./ intrinsic clearance of amprenavir is reduced by nelfinavir and indinavir but not saquinavir) depend on the extent to which one or both of these enzymes are affected. 

St. John s wort contains an enzyme inducer that can reduce the plasma concentrations of drugs that are substrates of CYP3A4, such as indinavir and ciclosporin. However, in eight healthy volunteers aged 24-43 years, St. John s wort 300 mg/day (0.3% hypericin standardized tablet) for 14 days had no effect on the pharmacokinetics of carbamazepine (110). 

Toxicity Nausea, diarrhea, thrombocytopenia, hyperbilirubinemia, and nephrolithiasis occur. To reduce renal damage, it is important to maintain good hydration. Indinavir is a substrate for and an inhibitor of the cytochrome P450 isoform CYP3A4 and is implicated in drug interactions. Serum levels of indinavir are increased by azole antifungals and decreased by rifamycins. Indinavir increases the serum levels of antihistamines, benzodiazepines, and rifampin. 

Trazodone is a substrate for CYP3A4 and inhibitors of this enzyme such as ritonavir and indinavir may inhibit its metabolism, leading to substantial increases in trazodone plasma concentrations with the potential for adverse effects. ... 

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