| Theophylline is a clinically useful, potent, bronchodilator, antiasthmatic agent available in the market as control release tablet dosage forms of 100mg, 200mg, 300mg, 400mg to provide several advantages over conventional dosage forms. Controlled release drug administration provides constant therapeutic effect with the administration of low dose which reduce side effects, improving patient compliance.;Solid dispersion technique was used to increase the dissolution and bioavailability of water insoluble drugs. Now a days this technology is being developed to enhance various issues of sustained release, improved solubility and stability. Presently availability of various polymers, innovative techniques of production and number of solvents support growth of solid dispersion technology in pharmaceutical industry.;The aim of the study was to provide long lasting effect of Theophylline in solid dispersion system by use of various polymers. Solid dispersion formulations were prepared using solvent evaporation method, using single and multiple carrier systems. Drug release profiles were determined by USP-I rotating basket method. XRD, DSC and FTIR studies were performed to evaluate the physical characteristics of prepared solid dispersion.;Solid dispersion containing Drug/KLUCELRTM (HXF) at ratio 1:1 w/w gave considerable drug release profile over extended period of time. On the other hand physical mixture of the same drug-polymer mixture were performed and compared with dispersion formulation, the result showed that drug release was only controlled with dispersion formulation. It proves formation of solid dispersion is the key which controlled the drug release in the formulation.;The feasibility of developing multiple strength dosage form of the same formulation were evaluated preparing 50 mg, 100 mg, 200 mg, 300 mg of (drug) solid dispersion powder. Dissolution profile and data revealed that percentage drug release and released pattern were similar regardless of dosage strength. It supports that a solid dispersion formulation is simple and convenient technique for designing the multiple strength dosage forms of this drug.;One of the most important objective of the study was evaluated physical characteristics of formulation powder using X-ray diffraction, Differential Scanning Calorimetric (DSC) and Fourier Transformed Infrared spectroscopy (FTIR) studies, support the evidence that there are no chemical interaction among drug and polymer and drug exists in the amorphous form. Furthermore, formulation was subjected for stability study, had no adverse effect of temperature and humidity on the drug release profiles. |
