If a new oral drug, designed to act on the central nervous system, exhibits a very high first-pass metabolism, which consequence follows?

💡 Explanation

High first-pass metabolism indicates that a significant amount of the drug is metabolized in the liver and gut wall before reaching systemic circulation, because this reduces the amount of unchanged drug that reaches its target. Therefore, the systemic bioavailability is significantly reduced, rather than increased brain penetration or altered clearance mechanisms.

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