[Influence of Storage Conditions after One-dose Packaging on Stability of Magnesium Oxide Tablets].

The intestinal motor function declines in the elderly. Many patients have constipation and ingest magnesium oxide for a prolonged period. One-dose packaging of drugs is adopted for many elderly patients to help them to avoid forgetting to take an increase in the number of oral drugs to be taken and improve convenience. Several studies on differences in stability among magnesium oxide preparations including generic drugs have been reported, but no study on the influence of the storage conditions after one-dose packaging on the properties of magnesium oxide tablets has been reported. Three types of magnesium oxide tablet were one-dose-packaged and stored for 12 weeks with and without a desiccant. The difference in hardness and weight significantly increased in all tablets stored without a desiccant. The disintegration time significantly extended in the tablets stored without a desiccant from 2 weeks after the initiation of storage and that of the B tablet markedly extended. However, all tablets passed the disintegration criteria of the disintegration test. The pH-area under the concentration-time curve significantly decreased in the tablets stored without a desiccant. It was suggested that when the one-dose-packaged magnesium oxide preparation is stored, it should be placed in a bag containing a desiccant.