EFFECTS OF PROPYLENE-GLYCOL DIESTERS OF CAPRYLIC AND CAPRIC ACIDS (MIGLYOL(R) 840) AND ETHANOL BINARY-SYSTEMS ON IN-VITRO SKIN PERMEATION OF DRUGS

Miglyol(R) 840, propylene glycol diesters of caprylic and capric acids , in binary systems with ethanol markedly improved the in vitro skin p ermeation rate of several transdermal drug candidates such as tetrahyd roaminoacridine (THA), diltiazem, atenolol, tazifylline and hydrocorti sone, as compared to ethanol or Miglyol(R) 840 alone across human and hairless mouse skin. The addition of ethanol to Miglyol(R) 840 improve d the drugs' skin permeation rates primarily as a result of increasing the drugs' solubility. The addition of ethanol to Miglyol(R) 840 also improved the relative permeation rate (permeation rate/initial concen tration) of ethanol. No local irritation (erythema or edema) was noted over a 24 h period among four human volunteers wearing patches contai ning the binary vehicle, ethanol: Miglyol(R) 840 (20:80) or ethanol: M iglyol(R) 840 (40:60).