title: Physicochemical characteristics of drugs and response to repeat-dose activated charcoal.
abstract: Although the administration of repeated doses of activated charcoal has been advocated to increase the systemic clearance of many drugs, it is unknown whether a drug's physicochemical properties are associated with enhanced removal by repeat-dose activated charcoal. The English language literature was searched to identify clinical studies evaluating repeat-dose activated charcoal. Percent reduction in plasma elimination half-life during repeat-dose activated charcoal was calculated and correlated with the drugs' characteristics. A step-wise multiple regression analysis with the independent variables of the drugs' molecular weight, pKa, plasma protein-binding, intrinsic plasma elimination half-life, and volume of distribution failed to identify potential predictors (P = .1) of effectiveness of repeat-dose activated charcoal. This analysis suggested that charcoal therapy was more effective for drugs with a longer intrinsic half-life (r2 = .24, P = .04). A uniform framework that evaluates the physicochemical characteristics of drugs and their response to repeat-dose activated charcoal is needed to better define which patients would benefit from repeat-dose activated charcoal therapy.
authors.affiliation: Southern Poison Center, Memphis, TN.
authors.forename: J W
authors.initials: JW
authors.lastname: Campbell
authors.forename: P A
authors.initials: PA
authors.lastname: Chyka
mesh_terms: D000328:Adult; D002606:Charcoal / Q000008:administration & dosage / Q000494:pharmacology*; D004334:Drug Administration Schedule; D006801:Humans; D010599:Pharmacokinetics; D011041:Poisoning / Q000188:drug therapy
chemical_list: D002606:Charcoal