• PHYSICAL STABILITY OF AMORPHOUS SOLID DISPERSION: A REVIEW

Abstract

Solid dispersions in water-soluble carriers have attracted considerable interest as a means of improving the dissolution rate, and hence possibly bioavailability, of a range of hydrophobic drugs. However, despite thevarious advantages of solid dispersion, the technique has some major drawbacks. One of the major problemis related to the physical stability of the high energy amorphous state of the drug. Since solid dispersion aids in the improvement of the dissolution and solubility, the drug in the amorphous state may get converted to the crystalline state with the time period. This review mainly focuses on the factors that help in the improvement of the physical stability of the solid dispersion. The implications of a deeper understanding of the physical stability are discussed, with particular emphasis on optimizing the ratio of carrier and drug, choice of the carrier, the prediction of the glass transition temperature of drug and the carrier and the mechanism involved in the physical changes of solid dispersions resulting in crystallization.