First-Pass Effect
The metabolism of an orally administered drug by the liver and/or gut wall before it reaches the systemic circulation. Drugs with high first-pass metabolism have low oral bioavailability despite good absorption.
示例
- Nitroglycerin (sublingual to bypass)
- Morphine (~70% first-pass)
- Propranolol (~75% first-pass)
您知道吗？
The metabolism of an orally administered drug by the liver and/or gut wall before it reaches the systemic circulation. Drugs with high first-pass metabolism have low oral bioavailability despite good …