Bitterness of the mixture of clarithromycin dry syrup and carbocisteine preparation-difference between branded and generic drugs

The purpose of this study was to assess the bitterness intensity and pH of the solutions of clarithromycin dry syrup (CAM-DS), carbocisteine preparation (CC), and the concomitant use of both drugs. We conducted 6 types of human gustatory sensation tests with 6 healthy male volunteers. As a result, there was almost no difference in the bitterness intensity of CAM-DS between the branded (the latest and former preparations) and the generic formulations. The bitterness intensity of CAM-DS (the latest and former preparations of the branded as well as the generic formulations) was almost equally enhanced by mixing it with either the branded CC-DS or the branded and the generic carbocisteine granule (CC-Gr). On this occasion, the enhancing the bitterness of the branded CAM-DS (latest and former preparation) was nearly avoided safely by dosage form's changing CC-DS or CC-Gr to the branded CC-Sy. However, unlike the branded CC-Sy, some generic CC-Sy failed to suppress the bitterness. Furthermore, it was proven that some generic CAM-DS were shown to exhibit bitterness when mixed with even branded CC-Sy. In conclusion, it should be noted that the extent of bitterness of the mixture of CAM-DS and CC highly varies among the generic formulations.