Reference

Percutaneous penetration of nicotinates: in vivo and in vitro measurements

Percutaneous penetration of nicotinates: in vivo and in vitro measurements. Guy, Richard H.; Carlstroem, Eva M.; Bucks, Daniel A. W.; Hinz, Robert S.; Maibach, Howard I. (Dep. Pharm., Univ. California, San Francisco, CA 94143, USA). J. Pharm. Sci., 75(10), 968-72 (English) 1986. CODEN: JPMSAE. ISSN: 0022-3549. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) The relationship between chem. structure and percutaneous absorption has been explored with nicotinic acid [59-67-6] and its Me [93-60-7], Et [614-18-6], hexyl [23597-82-2], and benzyl [94-44-0] esters. Skin penetration was measured in vitro across hairless mouse skin and in vivo in humans. In vitro, Me and Et nicotinates (when applied in acetone) were delivered into skin such that the stratum corneum barrier was effectively bypassed. The lipophilic esters, on the other hand, were not solubilized in this way and penetrated more slowly. Nicotinic acid penetrated poorly, yielding essentially zero-order skin transport kinetics. Tape-stripping expts., in which penetration was monitored across skin with no stratum corneum, confirmed these observations. In vivo absorption of the esters was detd. from the urinary excretion of total radioactivity following topical administration of 14C-labeled penetrant. Kinetic anal. of the data yielded rate consts., the ratio of which correlated acceptably with the penetrant octanol-water partition coeff. (K). The dependence of the rate consts. on K was interpreted in terms of the relative affinity of the substrate for the stratum corneum compared with the viable tissue; the relationship agrees well with a previous evaluation involving structurally unrelated mols.

Topical pharmaceuticals containing rubefacients

Topical pharmaceuticals containing rubefacients. Neumann, Hans Werner (Klein, Karl, Fed. Rep. Ger.). Ger. Offen. DE 3213782 A1 13 Oct 1983, 9 pp. (German). (Germany). CODEN: GWXXBX. CLASS: IC: A61K031-44; A61K031-16; A61K031-725; A61K037-56. APPLICATION: DE 82-3213782 8 Apr 1982. DOCUMENT TYPE: Patent CA Section: 63 (Pharmaceuticals) Topical formulations of analgesics, antipyretics, antihistamines, etc., contain rubefacients, H2O, an alc., and a solubilizer to form micelles of hydrophilic and lipophilic components. The active ingredients include 2-hydroxyethyl salicylate [87-28-5], menthol [1490-04-6], and camphor [76-22-2]. A prepn. that can be used to impregnate a cloth, which is packaged for individual use, consists of 2-hydroxyethyl salicylate 3.25, benzyl pyridine-3-carboxylate [94-44-0] 0.18, N-vanillyl nonanamide [2444-46-4] 0.06, iso-PrOH 51.10, camphor 1.00, menthol 4.50, cajeput oil 1.50, rosemary oil /0.50, pine oil 1.There are some commonly used reagents with their cas registry numbers 1490-04-6 and 87-28-5 in this article.00, melissa oil 0.40, EtOAc 2.50, Et nitrite 2.00, iso-Pr myristate 1.50, polyoxyethylene (20) sorbitan monooleate 3.00, and H2O 27.51 g. .