eng Science and Education Publishing American Journal of Pharmacological Sciences 2013-09-15 1 1 67 73 10.12691/ajps-1-4-5 AJPS2013145 article Praveen Kumar praveensha77@gmail.com 1 Chhater Singh 2 S. D. College of Pharmacy & Vocational Studies, Muzaffarnagar, India Shri Venkateshwara University Rajabpur, Gajraula, India It is generally recognized that poor solubility is one of the most frequently encountered difficulties in the field of pharmaceutics. Low solubility and subsequent unsatisfactory dissolution rate often compromise oral bioavailability. There are most therapeutic agents used to produce systemic effects by oral route that are the preferred way of administration owing to its several advantages and high patient compliance compared to other routes. However, poorly water-soluble drugs, when administered orally, have been shown to be slowly and unpredictably absorbed since their bioavailability is largely dependent on the dissolution process in gastrointestinal tract. This article demonstrates the various methods used to increase dissolution rates, preparation techniques of solid dispersion, and characterization methods of the solid dispersion. http://pubs.sciepub.com/ajps/1/4/5/ajps-1-4-5.pdf solubility bioavailability solid dispersion dissolution solvent evaporation method