The Effect of Temperature on Dianetral Compression Strength of δ-Phenylbutazone and Barbital (Form II) Tablets

Abstract

The effects of storage temperature on the diametral compression strength of δ-phenylbutazone and barbital (form II) tablets and on the drug dissolution rate were examined.For δ-phenylbutazone, it was found that the diametral compression strength, σ, increased but the specific surface area, S_w, decreased at high storage temperature. The dissolution rate showed a sharp decrease above 70°C. When the diametral compression strength, σ, was plotted against the rate of decrease in the specific surface area for phenylbutazone, a good linear relationship was observed. These findings can be explained by the sintering mechanism.In the case of barbital (form II), σ decreased and the dissolution rate increased at high temperatures. The specific surface area, S_w, however, exhibited no significant change with storage temperature. Barbital dose not appear to exhibit extensive sintering and the main mechanism involved is polymorphic transition.