Oral contraceptive failure occurs in patients receiving Rifampicin primarily due to____________?
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Answer: A. Rifampicin induce the metabolism of contra ceptive
Explanation
Rifampicin is a potent inducer of hepatic cytochrome P450 enzyme systems. Enzyme induction accelerates the biotransformation and clearance of concurrent medications. Oral contraceptive hormone levels drop below therapeutic thresholds, resulting in treatment failure. Cytochrome P450 induction increases the transcriptional synthesis of drug-metabolizing enzymes. Estrogens and progestins rely on hepatic clearance pathways for elimination. Accelerated hormone metabolism destroys the contraceptive efficacy protecting against pregnancy.
Female patients taking rifampicin require counseling regarding alternative non-hormonal contraception. Drug-drug interactions represent a major challenge in multi-drug antimicrobial therapy. Clinicians must review all concurrent medications before initiating enzyme-inducing antibiotics. Option B simulates gonadotropin release is incorrect since enzyme induction drives metabolism. Option C decrease secretion of progestin is wrong because metabolism is enhanced externally. Option D antagonize action is inaccurate because the mechanism involves accelerated drug clearance.
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