bioavailability 
noun [mass noun] Physiology
The proportion of a drug or other substance which enters the circulation when introduced into the body and so is able to have an active effect.These effects may profoundly affect the oral bioavailability of drugs....
- Clinicians and patients should beware of possible reductions in systemic bioavailability of conventional drugs when taken concomitantly with St John's wort.
- Systemic bioavailability secondary to lung bioavailability definitely occurs, but the contribution is insignificant.
Derivatives
bioavailable
- Vancomycin is poorly bioavailable when administered orally, and for systemic infections the intravenous route is used.
- As with other protein products, predigesting proteins facilitate absorption in the gastrointestinal tract, thus making the amino acids more bioavailable.
- It is not surprising that such complex species are not readily bioavailable, and are therefore not toxic.