The shelf life of some antibiotic preparations stored under tropical conditions.

Accelerated storage tests have been carried out to predict the shelf life of several commercial preparations stored directly under temperate and tropical climatic conditions. Two brands each of sulphathiazole tablets, tetracycline hydrochloride capsules and chloramphenicol capsules were studied over a period of three months. Shelf lives ranging from 6.2. to 29.7 months were predicted for temperate storage conditions (20 degree C/31% R.H.), whilst these periods were reduced giving values from 3.8 to 13.9 months for tropical conditions of 30 degree C/31% R.H and from 2.5 to 9.2. months when stored at 30 degree C/75% R.H. A decrease in the rate of drug dissolution was also observed for preparations stored directly under conditions of elevated temperature and humidity. The results indicate the need for stringent control over storage conditions for antibiotic preparations in tropical climates to ensure adequate drug stability and dissolution characteristics.