Compatibility between Sustained Release Fine Granules of Nifedipine and Drugs. (2).

The compatibility of combining sustained release fine granules of nifedipine (SRN) with 32 kinds of drugs was studied. The mixtures of SRN and drugs in heat-sealed packages (polyethylene-laminated glassine paper) were kept at either 20°C and 75% relative humidity (R. H.) or 30°C and 92% R. H. for 30 days, respectively. Any changes in the color or weight of the samples were recovered. Dissolution tests of nifedipine from the mixtures of SRN and drugs were studied in J.P. disintegration media No.1 and No.2. The dissolution of nifedipine was slightly enhanced in mixtures containing sodium bicarbonate in the disintegration medium No.1. However, no significant incompatibility was observed in the weight change, and no significant change was seen in the dissolution of nifedipine.