Due to its paramount adsorption capacity, activated charcoal is supposed to be the remedy of choice for binding a variety of drugs in the gastrointestinal tract. Hence it is surprising--at least according to the advice of German textbooks--that activated charcoal is only recommended for administration after time-consuming treatments like induced emesis and gastric lavage. Particularly with infants at home, a ready-for-use suspension of activated charcoal would allow the early management of acute poisoning. In such cases, inactivation of the poison by adsorption could be particularly helpful, since the period after ingestion is usually short. The charcoal-sorbitol-suspension (30 g activated charcoal in 150 ml of 70% sorbitol) is a creamy preparation which is easy to drink, because density and viscosity prevent sedimentation. The prescription-free drugs can be dispensed by each pharmacist. The present study was undertaken to investigate the influence of sorbitol on the adsorption capacity of activated charcoal. To this end, adsorption isotherms were established in vitro and compared with results in volunteers to whom NAPAP, diphenhydramine or codeine was administered separately. These drugs are gaining increasing importance in medicinal toxicology since they are constituents of various analgesics and cold remedies. To determine absorption, the cumulative urinary excretion was estimated of the parent drugs and their main metabolites.(ABSTRACT TRUNCATED AT 250 WORDS)