bioavailability


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bioavailability

 [bi″o-ah-vāl″ah-bil´ĭ-te]
the degree to which a drug or other substance becomes available to the target tissue after administration.

bi·o·a·vail·a·bil·i·ty

(bī'ō-ă-vāl'ă-bil'i-tē),
The physiologic availability of a given amount of a drug, as distinct from its chemical potency; proportion of the administered dose that is absorbed into the bloodstream.

bioavailability

(bī′ō-ə-vā′lə-bĭl′ĭ-tē)
n.
The degree to which or rate at which a drug or other substance is absorbed or becomes available at the site of physiological activity after administration.

bi′o·a·vail′a·ble (-lə-bəl) adj.

bioavailability

The rate and extent to which a drug is available to serve as a substrate, bind to a specific molecule or participate in biochemical reactions in a target tissue after administration. For oral agents, bioavailability reflects the rate and extent of GI tract absorption.

Bioavailability depends on the pI (isoelectric point), the pH of a solution in which the solute does not migrate (ionic form), presence of side chains or the conformation of the epitope. Bioavailability is affected by the route of administration, rate of metabolism, lipid solubility and binding proteins. It is usually < 100% due to degradation or alteration before reaching the target tissue.

bioavailability

Clinical pharmacology The degree to which a drug is available to a target tissue after administration which, for oral drugs, reflects the rate and extent of GI tract absorption; BA is the in vivo presence of a substance in a form that allows it to be metabolized, serve as a substrate, bind a specific molecule, or participate in biochemical reactions. See Oral bioavailability.

bi·o·a·vail·a·bil·i·ty

(bī'ō-ă-vāl'ă-bil'i-tē)
The physiologic availability of a given amount of a drug, as distinct from its chemical potency; proportion of the administered dose that becomes available to exert a pharmacologic effect into the bloodstream.

bioavailability

The amount of a drug that reaches the blood regardless of how it is given. After intravenous injection bioavailability is 100%, but the bioavailability of drugs given by mouth is often much less, because many drugs are broken down by the digestive enzymes and many are poorly absorbed.

Bioavailability

A measure of the amount of drug that is actually absorbed from a given dose.
Mentioned in: Antiretroviral Drugs

bi·o·a·vail·a·bil·i·ty

(bī'ō-ă-vāl'ă-bil'i-tē)
Physiologic availability of a given amount of a drug, as distinct from its chemical potency.
References in periodicals archive ?
Are you looking to improve drug performance, bioavailability and patient adherence?
The research team, led by Usha Zutshi, discovered that Piper longum (Piper species), in particular, acted to increase the bioavailability of many drugs (9, 10).
From an environmental and consumers perspective, a scalable technology that allows the formulation of supplements with less protein, higher bioavailability, and fewer calories can make protein production more sustainable and help create truly differentiated products for sports nutrition, weight management and clinical nutrition.
Thus, the GHD children--according to values of IGF-I/ IGFBP-3 molar ratio--were divided into two subgroups: lower IGF-I bioavailability and higher IGF-I bioavailability (see Materials and Methods).
The estimated relative bioavailability values obtained with the slope-ratio assay were 31.5% and 36.2% for BP and YP, respectively.
The scientists intend to determine the role that nano-laminated coating properties would play in the in vitro digestibility and release of lipids, and the impact of the composition and structure of nano-laminated coatings on the bioavailability of encapsulated lipids.
Three bioavailability studies were conducted as open, two- or three-period, two- or three-sequence crossover trials.
Why Only Modest Improvements in Bioavailability Have Been Achieved Thus Far
In the laboratory, the researchers also tested the bioavailability of beta-carotene from orange-fleshed honeydew melon tissue.
The comparative bioavailability study follows a positivescientific advice meeting with the German Federal Institutefor Drugs and Medical Devices (BfArM) announced by RedHill in November 2013.
Frutarom Switzerland, Health BU Switzerland, in conjunction with Aquanova AG, Darmstadt, Germany, is pleased to announce the results of a recently published human study examining the bioavailability of curcumin across three different oral delivery systems.