Shinya Uchida, PhD, received his Ph.D degree from University of Shizuoka in 1999. Dr. Uchida served as clinical pharmacist at University Hospital of Hamamatsu School of Medicine. He is associate professor at Univsersity of Shizuoka and his major interests include clinical pharmaceutical science, clinical pharmacology and pharmacokinetics. He has published more than 50 papers in reputed journals.


Orally disintegrating tablets (ODTs) disintegrate immediately in the mouth so that patients can take it without water. This characteristic of ODTs is beneficial for patients who have difficulty swallowing conventional tablets (CTs). Furthermore, ingestion of ODTs without water may be beneficial for patients with an overactive bladder (OAB) who have lower urinary tract symptoms and are thought to experience discomfort and inconvenience with water intake. Solifenacin (Vesicare®, VES) is an antimuscarinic agent for the management of OAB. This study aimed to determine the amount of water required for ingesting placebos of VES-ODT and of VES-CT. Healthy volunteers participated in this randomized crossover trial. The participants were asked to drink water during the intake VES-CT and after the disintegration of VES-ODT in their oral cavity. The amounts of water required for ingesting VES-CT and of VES-ODT were 42.8 mL and 20.0 mL, respectively, which indicated that the amount of water required for ingesting ODTs was significantly lesser than that for ingesting CTs. Furthermore, 5 (16.7%) participants did not require water for ingesting the ODTs. The amount of water required for taking 3 tablets was reduced with increasing the number of ODTs (1, 2 or 3 ODTs). Clinical disintegration time of VES-ODT was 21.4 sec in 10 healthy volunteers. This clinical disintegration time did not change significantly after unit-dose packaging or subsequent storage for 56 days. This study showed that the amount of water required for ingesting VES-ODT is lower than that for ingesting VES-CT.