Stability Studies of Phenylbutazone and Phenylbutazone-Antacid Oral Formulations

• Published in: Journal of pharmaceutical sciences 1978-05, Vol.67 (5), p.646-650
• Main Authors: Matsui, F., Robertson, D.L., Lafontaine, P., Kolasinski, H., Lovering, E.G.
• Format: Article
• Language: English
• Subjects: Antirheumatic agents-phenylbutazone; Antirheumatic agents—phenylbutazone various solid oral formulations, stability, effect of temperature and humidity; Degradation-phenylbutazone; Degradation—phenylbutazone various solid oral formulations, effect of temperature and humidity; effect of temperature and humidity; Phenylbutazone-various solid oral formulations; Phenylbutazone—various solid oral formulations stability, effect of temperature and humidity; stability; Stability-phenylbutazone; Stability—phenylbutazone various solid oral formulations, effect of temperature and humidity; various solid oral formulations
• ISSN: 0022-3549; 1520-6017
• DOI: 10.1002/jps.2600670519

Nineteen phenylbutazone and eight phenylbutazone-antacid solid oral formulations were stored in sealed bottles at room temperature and 37,50, and 60° with ambient relative humidity and at 37° with 75% relative humidity. Samples were examined for intact drug content, decomposition profiles, and dissolution rates at selected time intervals up to 296 days. None of the phenylbutazone formulations showed any evidence of chemical instability when stored at ambient temperature, 37°, and 37° with 75% relative humidity. Measurable chemical degradation occurred only at 60°, with several formulations showing more than 50% degradation by the time the study was terminated. In some formulations, the extent of degradation varied greatly among tablets within the same bottle and between bottles of the same lot. Shelflife could not be predicted from the data. The results indicate that the temperatures used in accelerated studies should not exceed 50°. Dissolution rates tended to decrease with time at 60° and, to some extent, at 37° with 75% relative humidity and 50°. Chemical degradation occurred at 37° in some phenylbutazone-antacid formulations and was general at 50 and 60°. At 60°. the extent of degradation approached a maximum during the initial time periods, suggesting that a reactant involved in the degradation had been consumed. There were no significant changes in the dissolution time of antacid formulations.