Bioavailability

Định nghĩa

The fraction of an administered drug dose that reaches systemic circulation in unchanged form. Intravenous drugs have 100% bioavailability by definition, while oral drugs are typically lower due to incomplete absorption and first-pass metabolism in the liver.

Ví dụ

Oral morphine has approximately 30% bioavailability because 70% is metabolized during first-pass through the liver.

Thuật ngữ liên quan

Half-Life t½ First-Pass Effect Area Under the Curve AUC

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