AN IN-VITRO EVALUATION OF COCAINE HYDROCHLORIDE ADSORPTION BY ACTIVATED-CHARCOAL AND DESORPTION UPON ADDITION OF POLYETHYLENE-GLYCOL ELECTROLYTE LAVAGE SOLUTION

Cocaine body-packers and body-stuffers have become a common medical pr oblem. Significant morbidity and mortality result when cocaine is abso rbed from the gastrointestinal tract due to cocaine package compromise . The clinical prevention of gastrointestinal absorption of cocaine in cludes oral activated charcoal and/or whole bowel irrigation with poly ethylene glycol - electrolyte lavage solution. This in vitro study inv estigates the maximal adsorptive capacity of activated charcoal for co caine at varying activated charcoal:cocaine ratios, at pH 1.2 and pH 7 .0, and the effect of polyethylene glycol - electrolyte lavage solutio n upon this binding. The percent adsorption of cocaine to activated ch arcoal was significantly better at pH 7.0 for all ratios of activated charcoal:cocaine tested and the maximal adsorptive capacity was 29% gr eater at pH 7.0 (273 mug/mg) than at pH 1.2 (212 mug/mg) (p < 0.05). A ddition of polyethylene glycol - electrolyte lavage solution to the co caine-activated charcoal slurry caused significant desorption of cocai ne from activated charcoal at all pHs and ratios tested (except the 1: 1 ratio at pH 7.0) and was most pronounced at pH 1.2. The addition of polyethylene glycol - electrolyte lavage solution to activated charcoa l prior to adding cocaine solution further decreased the adsorption of cocaine to activated charcoal. This difference was significant at bot h pHs and all ratios tested except the 1:1 ratio at pH 1.2. The maxima l adsorptive capacity of activated charcoal for cocaine at pH 1.2 was reduced 75% by pretreatment with polyethylene glycol - electrolyte lav age solution from 212 to 54.2 mug/mg, while at pH 7.0 the maximal adso rptive capacity was reduced by 11%, from 273 to 243 mug/mg. Polyethyle ne glycol - electrolyte lavage solution significantly reduces the adso rption of cocaine to activated charcoal particularly if the two are co mbined at a low pH prior to the addition of cocaine. The in vitro effe cts suggest that activated charcoal mixed in water should be administe red first, followed by the polyethylene glycol - electrolyte lavage so lution.