ISSN:
1573-8744
Keywords:
rate of absorption
;
rate of renal reabsorption
;
extraction theory
;
partition coefficientin vivo
;
pH of lumenal contents
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Equations have been derived which quantitatively describe the rate of gastrointestinal and buccal absorption of acidic and basic drugs as a function of pH of aqueous lumenal contents and time. The equations have been used to fit observed data in the literature, and the estimated parameters are reported. An equation which describes the renal clearance of an acidic or basic drug as a function of urinary pH is also derived. In essence, the equations quantitate the pH-partition hypothesis and explain most, if not all, related observed data in the literature. The results suggest that the aqueous diffusion layer may not rate-limit absorption of monomeric drug molecules but that absorption is rate-limited by transfer of drug out of the membrane in vivo.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01060026
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