Absence of ice‐cream interference with the adsorption of paracetamol onto activated charcoal

Abstract Aims: To measure the extent to which the addition of ice‐cream to activated charcoal interferes with its ability to adsorb paracetamol. Method: Activated charcoal, ice‐cream and both charcoal and ice‐cream were added to stock solutions of paracetamol at both simulated gastric and intestinal pH at charcoal : paracetamol ratios of 3:1, 5:1 and 10:1. The samples were centrifuged and the supernatant assayed for paracetamol concentration. Results: When the charcoal : paracetamol ratio was 3:1, charcoal alone adsorbed 65% of the available paracetamol, and charcoal with ice‐cream adsorbed 57%. When the ratio was 5:1, charcoal alone adsorbed 92% of the available paracetamol and charcoal with ice‐cream 90%. When the ratio was 10:1, charcoal alone adsorbed 100% of the available paracetamol and charcoal with ice‐cream 99%. The results were independent of pH. Conclusions: The practice of adding ice‐cream to activated charcoal to improve palatability does not decrease the ability of the charcoal to adsorb paracetamol in vitro, especially if charcoal : drug ratios are above 5:1.