If a drug with high hepatic extraction is administered orally but shows unexpectedly high bioavailability, which mechanism explains this observation?

💡 Explanation

High hepatic extraction typically results in low oral bioavailability due to the first-pass effect. However, if the drug bypasses the liver, it avoids this initial metabolism. Therefore, bypassing the hepatic first-pass effect will lead to higher bioavailability, rather than changes in renal, tubular, or biliary clearance mechanisms.

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