Development and optimization of guaifenesin sustained release mini-tablets for adult and geriatric patients

<b>Aim:</b> The main aim of this study was to formulate and optimize sustained release mini-tablets of guaifenesin.<b>Materials & methods:</b> Guaifenesin granules were successfully prepared using different blend ratios of carnauba wax to drug by melt granulation method. The properties of granules were further modified by combining them with ethyl cellulose. The obtained granules were then mixed and compressed into mini-tablets using a tablet press machine. The resulting mini-tablets were characterized in terms of weight, thickness, hardness, drug content and <i>in vitro</i> drug release.<b>Results:</b> Mini-tablets with 1:6 carnauba wax to drug ratio showed superior physicochemical characteristics, releasing about 100.03% of guaifenesin over 8 h. Ethyl cellulose offers a great potential to accurately control drug release from mini-tablets.<b>Conclusion:</b> The prepared mini-tablets seem to be a very promising alternative to guaifenesin conventional formulations and can be used in adults and elderly people.