stability evaluation of amoxicilliin and potassium clavulanate tablets usp by accelerated studies

Stability evaluation of amoxicillin and clavulanate potassium tablets was performed as per ICH guidelines Q1A (R2). The various parameters analysed include description, assay, dissolution, water content, water activity and shelf life determination. These parameters were evaluated at zero month, 1st month, 2nd month, 3rd month and 6th month intervals. The conditions under which these parameters were analyzed include RT and accelerated conditions. The description of the tablets was evaluated as per the specifications for the time periods specified. It has been observed that there is no significant change in the description of the tablets. The assay of amoxicillin and clavulanic acid was carried out using USP HPLC method, which is designated as stability indicating method because of its capability to distinguish the degraded product with the parent one. The results of assay indicate that the tablets are within the allowable limits (90 - 120 %).The dissolution studies were carried out for the specified time intervals to study the effect of accelerated temperature and humidity on the % of drug release from the tablets. The results of the dissolution study indicate that there is no significant change in the % of drug release. The water content was determined using Karl-Fischer titrator to evaluate loss of water at higher temperatures and water uptake at higher humidity conditions. The water activity was verified using Hygrolab water activity analyzer to know the hygroscopicity of the sample at accelerated conditions. The shelf life of the tablets was found to be 48.2 months by the linear regression analysis of the stability data generated. In view of the results obtained that amoxicillin and clavulanate tablets tested are recommended to be stored at 25°C and the stability of the tablets confirmed the ICH & USFDA guidelines.