The effect of food and ice cream on the adsorption capacity of paracetamol to high surface activated charcoal: in vitro studies

The effect of added food mixture (as if food was present in the stomach of an intoxicated patient) or 4 different types of ice cream (added as a flavouring and lubricating agent) on the adsorption of paracetamol (acetaminophen) to 2 formulations of activated charcoal was determined in vitro and compared with results from previous investigations showing a maximum adsorption capacity to the two activated charcoal-water slurries at about 0.62-0.72 g paracetamol/g activated charcoal. Activated charcoal (Carbomix or Norit Ready-To-Use), simulated gastric (pH 1.2) or intestinal (pH 7.2) fluid, and paracetamol were mixed with either food mixture or ice cream followed by one hr incubation. The maximum adsorption capacity of paracetamol to activated charcoal was calculated using Langmuirs adsorption isotherm. Paracetamol concentration was analyzed using high pressure liquid chromatography. In the presence of food, the paracetamol adsorption capacity of the 2 activated charcoals was reduced by max. 19% (P<0.05) for Carbomix(R) and by max. 11% (P<0.05) for Norit Ready-to-use compared to control without food (Hoegberg et al. 2002). Depending on which type of ice cream was mixed with the charcoal, the reductions compared to control (Hoegberg et al. 2002) varied between 11% and 26%. Even though a reduction in drug adsorption to activated charcoal was observed when food mixture or ice cream was added, the remaining adsorption capacity of both types of activated charcoal theoretically was still able to provide an effective gastrointestinal decontamination.