Effect of Taste Additives on the Palatability of Activated Charcoal: a Systematic Review

Activated charcoal is a decontaminating agent used for acute intoxication. It can be mixed with taste additives to overcome its poor palatability. Our purpose was to evaluate the taste additives used to improve activated charcoal's palatability.

We conducted a systematic review of comparative studies on taste additives used to improve activated charcoal's palatability. We searched PubMed, Embase, Web of Science, Cochrane, and CINAHL. We included controlled trials and observational studies that evaluate the effect of at least one taste additive, compared with activated charcoal alone. Our primary outcome was palatability. Our secondary outcomes included treatment adherence, adsorption efficacy, and adverse events. The risk of bias was assessed using the Quality Assessment Tool for Quantitative Studies.

Among 38 eligible articles, seven observational studies and three crossover clinical trials met our inclusion criteria. The risk of bias was found to be high for seven studies and intermediate for three others. The preferred flavoring agents were cola and chocolate milk for children, and sweetening agents for adults. All taste additives studied seemed to improve activated charcoal's palatability, except for yogurt (n = 1). The addition of bentonite, sorbitol, carboxymethylcellulose, or yogurt showed no impact on the in-vivo adsorption capacity of activated charcoal, whereas the results were inconclusive for chocolate. No meta-analysis was performed due to insufficient data.

Strategies to improve activated charcoal's palatability seem to enhance the taste. Descriptive data are in favor of a limited impact on activated charcoal's adsorption capacity when adding binding agents or sweeteners.

This review is registered as PROSPERO CRD42019135092.