[Stability of nilvadipine solid dispersion tablet with non-packaging condition].

Nilvadipine (NIL) solid-dispersion tablets were stored counter to packaging instructions by exposing them to 40 degrees C, 25 degrees C, 75% relative humidity, and light. The dissolution, stability assay, and tablet properties (weight, thickness and hardness) were then examined. NIL dissolved more than 85% after all storage periods with exposure to high temperature and humidity. Powder X-ray diffraction analysis indicated that NIL was present in an amorphous state as in the initial state. The stability assay of NIL showed that it was more than 99% stable during all storage periods when exposed to temperature, humidity, and light, indicating good stability. Tablet properties were influenced by humidity more than by temperature, and the hardness of tablets decreased with time to 42.9 N after storage of 3 months.