Bioavailability [Food and Drugs] Law and Legal Definition

Pursuant to 21 CFR 320.1 (a) [Title 21 Food and Drugs; Chapter I Food and Drug Administration, Department of Health and Human Services; Subchapter D Drugs for Human Use; Part 320 Bioavailability and Bioequivalence Requirements; Subpart A General Provisions], Bioavailability means “the rate and extent to which the active ingredient or active moiety is absorbed from a drug product and becomes available at the site of action. For drug products that are not intended to be absorbed into the bloodstream, bioavailability may be assessed by measurements intended to reflect the rate and extent to which the active ingredient or active moiety becomes available at the site of action.”