* IQVIA Global OTC Insights, R5C Expectorants, excluding combinations with antitussives + 01A3 Dry Cough Products + 01A4 Expectorants + 01A5 Dry Cough and Expectorant Products, Sales, Data as of MAT 12/2021
** Lang et al., Planta Medica, 81(12/13), 968-974.