Speed at which a drug enters the bloodstream is called what?

• A. Absorption rate
• B. Routes of administration
• C. Dosage
• D. How supplied

Answer: (A)

The speed at which a drug enters the bloodstream is described by the absorption rate. This reflects how quickly the drug moves from its site of administration into systemic circulation, which in turn influences how soon effects begin. In pharmacology, absorption rate is a key factor in determining onset of action. The route of administration plays a big role: intravenous administration delivers drug directly into the bloodstream for essentially immediate effect, while intramuscular or subcutaneous routes allow slower absorption, and oral administration often has variable, slower absorption due to digestion and first-pass metabolism. The dosage is about how much drug is given, not how fast it enters the blood, and how supplied refers to the formulation or packaging, not the kinetic process of absorption.