Bioavailability — What It Means in Clinical Trials
Plain English Definition
Bioavailability measures how much of a drug actually reaches your bloodstream and is available to work. A drug given by injection has 100% bioavailability because it goes directly into your blood. A pill has lower bioavailability because some of it is lost during digestion.
Why It Matters
Bioavailability affects dosing. If a drug has low bioavailability, you may need a higher dose by mouth to get the same effect as a smaller injected dose. Some trials compare pill versus injection forms of the same drug.
Example
A study might investigate: "Bioavailability of oral formulation compared to intravenous administration" to determine if a pill version could replace an infusion.
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