ABSTRACT
Sekiguchi and Obi (1961) introduced the use of solid dispersion (SD) technology to the pharmaceutical industry as a formulation approach to prepare immediate release (IR) oral dosage forms of poorly water-soluble drugs. Solid dispersions have also been used in extended release oral dosage forms, but the scope of this review is limited to the IR applications. The primary reason to develop a SD is to enhance dissolution and improve the oral bioavailability of a poorly water-soluble drug. Solid dispersion for mulations are not appropriate where a drug has low bioavailability due to either metabolism or poor permeability. Many studies on SDs have been reported, and sig nificant improvement in the in vitro dissolution of poorly water-soluble drugs has been frequently demonstrated. Previous literature reviews include Chiou and Riegelman (1971b); Corrigan (1985); Ford (1986); McGinity and Coffin (1990); and Vadnere (1990). The clinical relevance has been examined, and improvements in the extent of absorption have been observed (Barrett and Hanigan 1975; Chiou and Riegelman 1971a; Doherty and York 1989a; Sheen et al. 1991).
