Stability study of nitroglycerin sublingual tablets

Nitroglycerin sublingual tablets were studied over a 1-year period to determine tablet stability in terms of loss of strength, uniformity of tablets, and degradation of the drug itself. Tablets from six different firms were analyzed by a semiautomated procedure. The samples included two molded tablets and four compressed tablets, ranging in age at the time of initial assay from 40 days to over 1 year. The results indicated that there is a loss of strength of nitroglycerin tablets and that refrigeration slows down this loss. The study also indicated that these tablets were stable during the year of testing in terms of tablet uniformity and degradation of nitroglycerin.