Sustained-release matrix tablets of terbutaline sulphate: Formulation and in vitro evaluation

The objective of the present study was to develop sustained release matrix tablets of Terbutaline Sulphate used in asthma. The tablets were prepared by wet granulation method using isopropyl alcohol with stearyl alcohol as granulating agent. Hydrophilic matrix materials like Hydroxypropyl methylcellulose (HPMC), hydrophobic polymer such as Eudragit RLPO where used in the study. The granules were evaluated for angle of repose, bulk density, compressibility index, Swelling index, and drug content. The tablets were subjected to thickness, diameter, weight variation test, drug content, hardness, friability, and in vitro release studies. The granules showed satisfactory flow properties, compressibility and drug content. The results of dissolution studies indicated that optimized formulation F-5 (drug with HPMC 4KM), E-5 (Drug with HPMC 10 KM), S-5 (Drug with Eudragit RLPO) could extend the drug release up to 12 h. These optimized formulation showed similar release profile as that of the marketed product. All the formulations exhibited Higuchi-dominated drug release. The mechanism of drug release was found to be diffusion controlled.