Relative bioavailability

The bioavailability relative to a reference or standard formulation or agent. 

Peptide or Protein (Amino-acid Length) Dosage Confignration Device Bioavailability (Relative to IM or SC Route) References... 

Buccal delivery of opioid analgesics and antagonists can improve bioavailability relative to the oral route. Esterification of the 3-pheno-lic hydroxyl group in opioid analgesics such as nalbuphine, naloxone, naltrexone, oxymorphone, butorphanol, and levallorphan improved bioavailability and eliminated the bitter taste. The prodrug of morphine,... 

Absorption also takes place in the second section of the small intestine, known as the jejunum, and in the third section, known as the ileum. Digestion and absorption are complete by the time the ingesta have reached the terminal end of the ileum. This area is therefore of interest to researchers studying nutrient bioavailability (relative absorption of a nutrient from the diet) since a comparison of dietary and ileal concentrations of a nutrient provides information on its removal from the gut during digestion and absorption. 

The bioavailability of sustained released formulation of etodolac is about 80% of that of an oral solution in healthy male subjects [18]. Etodolac from tablets and capsules is 100% bioavailable relative to oral solution... 

Chitosan microspheres were shown to enhance nasal bioavailability of several peptide drugs such as insulin and goserelin. A simple chitosan-insulin powder formulation provided about 20% of absolute insulin bioavailability in sheep [96], Improved bioavailability (of 44%, in rats) was obtained when insulin was loaded into chitosan microspheres prepared with ascorbyl palmitate as cross-linking agent [91]. Chitosan microspheres have also been shown to improve nasal goserelin absorption providing about 40% bioavailability relative to goserelin intravenous application [9],... 

Absolute bioavailability Relative exposure (Cirrho tics/contro 1) ... 

CCK-B selectivity is improved over that of L-365,260 (507, 508). The pyridyl group in (125) provides a significant enhancement in oral bioavailability relative to the phenyl analog. Replacement of the 3-methyl group in (125) with basic moieties (NHMe, NMe2) likewise maintains the receptor binding profile and enhances oral bioavailability (509). 

An interesting example of polymorphic structure differentiation is that of human immunodeficiency virus (HIV) protease inhibitors. The HIV protease inhibitors pose a serious problem in their bioavailability. Invirase showed only modest market performance, and it was soon superseded by drugs, such as ritonavir (Norvir) and indinavir sulfate (Crixivan ) that had better bioavailability. Three years after initial approval, saquinavir was reintroduced in a formulation with sixfold higher oral bioavailability relative to the original product. Ritonavir was originally launched as a semisolid dosage form, in which the waxy matrix contained the dispersed drug in order to achieve acceptable oral bioavailabiUty. Two years after its introduction, ritonavir... 

Frequently, however, the standard is an innovator product or another established product. If the (AUC)q values are identical following the administration of equal doses of the test and reference products, we conclude that the test product is completely bioavailable relative to the standard. It is essential to use the term relative to the standard, because we do not know if the standard is completely absorbed or available. Additionally, when two products produce comparable peak plasma... 

PN-glucoside serves as a source of nutritionally available vitamin Be, with 50% bioavailability relative to PN (Maeno et al. 1997 Nakano et al. 1997). 

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