Penetration of Sulfonamides Through Intact Skin by Iontophoresis and other Means of Local Application

Abstract

The mechanism of action of the sulfa compounds and probable explanations for their inhibition by various factors are thoroughly discussed in recent papers by Long,4 by Kohn and Harris.' aiid by Harris and Kohn.G Presumably the same reasoning may be applied to parariitrobenzoic acid.Conclusion. The bacteriostatic effect of l)aratiitrohenzoate on the pneumococcus is markedly reduced by the products of disintegrating tissue. From the Depnrtment of ~o o l o~/ !~ urril tlie Di/ii.sion of Dprvmtology aid ,S.yphilolo.qy, Uniuersity of Xin,mesota, and tkc. Depnrtmvit of Derrnutoloyy awl Syphilology, -If inriea pol is Gc ti ern I Hospital.r -I his report prescnts sonie prelimiiiary studies in wliicli penetration by topical application o t' various sul fonamides has heen nieasured by tissue analysis. It was thought that iontophoresis (electrolytic ion transport) iriiglit be ail effective mcaiis of forcing the aiiioti o f sulfonaniide salts into the skin. l'eiietration hy iontoplioresis was, therefore, coinpared with that from wet dressings and from ax1 ointnieiit, in the rat, ralhit, and liunian. The effect o f circulation and the depth o f penetration were estimated.Mctlzotis. The expcririimtal ani~nals were anesthetized with iieriihutal anti the liair renioved with clippci-s. Iii the ivtitophoresis cxperiments, ('anton flaiiiicl ( 6 o x grade') was wetted with the test soliitio~i a i i d applied to tlie skin. Metal gauze electrodes were firmly applied over tlie flaiiiiel as the negative p l c . The positive electrode was applied to one o f the extremities. and curretits of 1-2 tnilliamperes at 110-125 volts I>.('. were applicrl.Peiietratioii from w t dressings (gauze (11-tlaiiriel j witliout current passage, was similarly studied in coiiipar"t1)lc areas on thc same animal or on different aniiiials. 4Long, P. H., Slgnia Xi Q u , n r t~~l y , 1941, 29, 149.