Bioavailability (BA): Definition and Objectives

Bioavailability BA definition and objectives explain the rate and extent of drug absorption reaching systemic circulation.

Bioavailability (BA) definition and objectives

Definition of Bioavailability

• Bioavailability is defined as the fraction (F) of an administered drug dose that reaches systemic circulation in an unchanged form and is available for therapeutic action. It includes both:
  • Extent of drug absorption (how much drug reaches systemic circulation)
  • Rate of absorption (how quickly the drug reaches systemic circulation)

Objectives of Bioavailability Studies

• Bioavailability studies are conducted to:
  1. Compare Different Drug Formulations – Ensure consistency between different formulations of the same drug.
  2. Evaluate Drug Absorption – Assess how much drug enters the bloodstream after administration.
  3. Determine Optimal Dosage Forms – Choose the best formulation (tablet, capsule, solution, etc.).
  4. Assess the Impact of Food or Other Factors – Understand how food, pH, or metabolic variations affect drug absorption.
  5. Establish Therapeutic Equivalence – Ensure generic formulations provide the same therapeutic effect as brand-name drugs.

Click Here to Watch the Best Pharma Videos!