Purpose: The effect of dilution with beverages on the smell and taste of oral acetylcysteine was studied.
Methods: A 5% solution of acetylcysteine was prepared from a 20% solution using water, Fresca, Coca-Cola, cranberry juice, or chocolate milk. Adult pharmacy students blinded to the diluent used a visual analogue scale (VAS) to rate the smell and taste for each 5% solution. For the taste evaluation, approximately 10 mL of each 5% solution was placed in a cup with a lid and straw. The difference in VAS scores for taste and smell was measured using the Kruskal-Wallis rank sum test. Comparisons were performed using the Mann-Whitney U test and the Bonferroni adjustment, with the level of significance set at <0.005.
Results: A total of 42 adult students participated in the study. Fresca was rated as the least offensive diluent with respect to smell by 22 students (52%) and taste by 33 students (79%). The chocolate milk-acetylcysteine solution was rated as the most offensive smelling by 22 students (52%) and most the offensive tasting by 11 students (26%). Cranberry juice was rated the most offensive tasting by 12 students (29%). The VAS score for Fresca was significantly lower than for all other beverages with respect to both smell and taste (p < 0.005).
Conclusion: Acetylcysteine 20% oral solution diluted with Fresca to a 5% solution was reported to have the least offensive odor and taste and should be considered as an option when attempting to improve the palatability of oral acetylcysteine to adults.