Bitterness evaluation of intact and crushed Vesicare orally disintegrating tablets using taste sensors

Objective

Vesicare tablets, whose main component is solifenacin succinate, are known to be extremely bitter. The purpose of this study was to evaluate the effect of crushing on the bitterness of the Vesicare orally disintegrating tablets (ODTs).

Method

Vesicare ODTs and conventional Vesicare tablets (CTs) were crushed either heavily or lightly. The bitterness scores and release rates of sample solutions obtained 5, 10, 30, 60, 90 or 120 s after placing a crushed CT or ODT containing 5 mg solifenacin in 40 ml of water were predicted using two taste sensors (SA402B and a-ASTREE) and HPLC, respectively. The particle size and the surfaces of the crushed tablets were observed microscopically.

Key findings

The predicted bitterness scores and the drug release rates of CTs were high, irrespective of the degree of crushing. The lightly crushed ODT was predicted to be less bitter than the heavily crushed ODT. In lightly crushed ODTs, spherical particles were observed, about 200 mm in diameter.

Conclusions

The degree of crushing was a critical factor in determining the expression of bitterness by crushed ODTs. When intact tablets of Vesicare must be crushed to adjust the dosage, it is strongly recommended that ODTs be crushed gently.

Suppression of bitterness and improvement of palatability of commercial prednisolone powder

The aim of the study was to suppress the bitterness and improve the palatability of pediatric prednisolone powder (PP) by the addition of simple sucrose syrup (SS) and various beverages and foods. Bitterness suppression was evaluated using the human gustatory sensory test. The suppression of the bitterness and improvement of palatability of PP by addition of SS solutions was investigated using standard taste substances: sucrose for sweetness, tartaric acid for sourness, and sodium chloride as saltiness. Dilution with SS solutions of up to 50% (w/w) was successful in bitterness-suppression and improvement of palatability, but at 80% (w/w) SS, the palatability of the diluted solution was reduced. The kinematic viscosities of SS solutions were therefore evaluated using the Uberorde viscosity meter, to see whether the high viscosity of the more concentrated solutions was responsible for the reduced palatability. The kinematic viscosity of the 80% SS was 16.60 mm(2)/s. Judging from above information, the palatability might become worse when the kinematic viscosity of syrup exceeded 15 mm(2)/s. Finally, the ability of various beverages and foods with low viscosity to suppress the bitterness and improve the palatability of PP were examined. The additions of orange juice or a carbonated lemon drink to simple syrup solution were most effective in suppressing bitterness and improving palatability of PP.

Quality of twelve clarithromycin dry syrup formulations-bitterness, grittiness and uniformity of drug loading

The objective of the study was to evaluate the bitterness, grittiness and uniformity of drug loading as measures of the quality of 12 formulations of clarithromycin dry syrup (CAMDS), comprising one branded and 11 generic products. Some of the generic CAMDS formulations were more bitter than the branded product while others had similar bitterness when tested as aqueous suspensions. Only one generic product was less bitter than the branded product when tested as a suspension in acidic sports drink. The usual dissolution test described in JP XV could not be used to evaluate the bitterness of the products. A brief dissolution test using only 12.5 ml of water was used to evaluate the bitterness of the products in aqueous suspensions. There were considerable variances in the grittiness of the various products, which were independent of particle size. Changes in grittiness level seemed to be correlated with changes in the intensity of bitterness due to the disintegration of the formulation. Finally, there was less variation in the uniformity of drug loading for the branded product than for the generic products. These data may be useful when selecting which CAMDS formulation to prescribe.