First-Pass Effect

Pharmacokinetics

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.

أمثلة

  • Nitroglycerin (sublingual to bypass)
  • Morphine (~70% first-pass)
  • Propranolol (~75% first-pass)

هل تعلم؟

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 …