Antipyrine factors

Fraser, H. S., Mucklow, J. C. et al. (1979). Environmental factors affecting antipyrine metabolism in London factory and office workers. Br. J. Clin. Pharmacol., 7(3), 237-43. 

The consideration of clearance in units of volume per maximum life span potential, instead of the traditional volume per weight, provides an allometric relationship for drugs such as antipyrine and phenytoin [17]. Both of these dmgs are essentially low clearance compounds, cleared by P450 metabolism. Ultimately, the successful utility of such factors may be purely serendipitous as they simply exploit unique features of man as a species. 

Two factors combine to lend a greater diversity in the stereochemistries exhibited by bivalent germanium, tin and lead compounds, the increased radius of Mn compared with that of Mw and the presence of a non-bonding pair of electrons. When the non-bonding pair of electrons occupies the isotropic valence level s orbital, as in, for example, the complex cations Pb[SC(NH2)2]6+ and Pb[antipyrine]6+, or when they are donated to conductance band levels, as in the binary tin and lead selenides or tellurides or the perovskite ternary phases CsMX3 (M = Sn, Pb X = Cl, Br, I), then the metal coordination is regular. However, in the majority of compounds an apparent vacancy in the coordination sphere of the metal is observed, which is usually ascribed to the presence of the non-bonding pair of electrons in a hybrid orbital and cited as evidence for a stereochemically active lone pair . 

In an earlier study using multiple regression analysis to determine the basis of interindividual variations in antipyrine clearance among 49 Gambians (29), the principal causative factor identified was the number of cola nuts chewed per day (r = 0.4). However, in a prospective study on an entirely different population of carefully controlled, environmentally stable normal male subjects... 

Secondly, this method fails to account for the majority of the intersubject variability in antipyrine disposition that exists among even those few subjects in whom the method has been applied. For example, when smoking and oral contraceptive use were considered alone (33), only 9% of the total variance in antipyrine kinetics among 207 normal volunteers was accounted for none of the other factors examined by multiple regression analysis could provide a clue as to what was responsible for the other 91 of the variance. 

The multitude of factors contained within the environment which may influence drug disposition and metabolism are difficult to separate. The finding that race and diet may affect the clearance of drugs such as antipyrine is such an example. Thus, meateating Caucasians have a significantly greater clearance and a shorter plasma half-life for antipyrine than Asian vegetarians. However, the relative importance of race versus diet as contributions to those differences is not clear. 

Lurie, I.S. Demchuk, S.M. Optimization of a reverse phase ion-pair chromatographic separation for drugs of forensic interest. I. Variables affecting capacity factors. J.Liq.Chromatogn, 1981, 4, 337-355 [acetylcodeine, acetylmorphine, aminopyrene, aminopyrine, amobarbital, antipyrine, butabarbital, diamorphine, methapyrilene, morphine, narcotine, papaverine, pentobarbital, phenobarbital, quinidine, quinine, secobarbital, strychnine, thebaine]... 

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