Dojin Iyaku-Kako Co., Ltd.

Bergenin (I) [477-90-7] was more readily absorbed from the digestive tract of the rat when administered as in the Na salt rather than as the free base.The absorption rate in the small intestine was greater than in the stomach.The rate was also greater at alkaline than acidic pH values.

Bergenin (I) [477-90-7] had a dose dependent antisecretory effect on gastric secretion in pylorus ligated rats for 3-6 hr.The ED50 for gastric secretion in pylorus ligated rats for 6 hr was 210 mgI/kg for free acidity, 240 mgI/kg for total acidity, and 260 mgI/kg for gastric juice volumeI not only had dose dependent antiulcerogenic activities in rat stress-induced ulcers, but also had the same effect on exptl. ulcers induced by serotonin, reserpine, and fasting.The ED50, for exptl. ulcers from reserpine, serotonin, stress, and fasting were 64, 32, 38, and 38 mg/kg.

Understanding the relationship between the release characteristics of the active ingredient in the tape formulation and the pharmaceutical characteristics of the adhesive layer can optimize therapeutic efficacy and improve patient adherence. This study aimed to clarify the effect of liquid paraffine (LP)/styrene-isoprene-styrene (SIS) triblock copolymer ratio on pressure-sensitive adhesive (PSA) formulation properties, such as adhesive properties and drug release, with a certain amount of diclofenac sodium (DFS) and tackifier. The effects of changes in PSA composition in DFS-containing tape formulations on adhesive and drug release properties were evaluated. The viscoelasticity results showed rigid gel-like behavior at low angular frequencies regardless of the LP/SIS ratio, and deformable gel-like behavior at high angular frequencies, with a maximum plasticizing effect of LP up to an LP/SIS ratio of 3.7. The peel adhesion test results showed that peel adhesion was not affected, but indicated a decreasing trend by increasing the LP/SIS ratio in the presence of DFS. Drug release test results showed that DFS release increased up to 24 h for LP/SIS ratios of up to 3.7, but decreased when the LP/SIS ratio was 6. The results of the drug permeation tests were similar to those of the drug release tests. In conclusion, it is possible to change the drug release properties by changing the amount of LP in the tape formulation; however, no definitive correlation was found between the adhesive and drug release properties.