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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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OCP's are contraindicated in women receiving which of the following drug ?
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The correct answer is  OCPs are contraindicated in patient on enzyme-inducing drugs like rifampicin, and antiepileptic except sodium valproate. Rifampicin induces cytochrome 450 ,increasing the hepatic hydroxlation of estrogen by which there is a fourfold increase in its metabolism. This causes clearance and deceased effect of estrogen. Reference: Shaw's textbook of Gynaecology 17th edition,page 265.