Rifampicin Erlotinib

ERLOTINIB ANTIBIOTICS - RIFAMPICIN 1 erlotinib levels Rifampicin t metabolism of erlotinib Avoid co-administration... 

Pretreatment with rifampicin 600 mg once daily for 7 days reduced the AUC of erlotinib by about 66%. In another study, the AUC of a single 450-mg dose of erlotinib, taken after 11 days treatment with rifampicin was about 57% of that of erlotinib 150 mg taken without rifampicin. The manufacturers advise that alternative treatments with no cytochrome P450 enzyme-inducing activity should be considered. If this is not possible, the starting dose of erlotinib should be adjusted to 300 mg (UK) with close monitoring, and, if tolerated, further increased after 2 weeks, in 50 mg increments, to 450 mg. They also advise caution with other CYP3A4 inducers, and specifically name barbiturates, carbamazepine, phenobarbital, phenytoin, rifabutin, rifapentine, and St John s wort. 

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