Approaches for the Improvement in Solubility and Dissolution of Poorly Water Soluble Drugs: A Review

Poor aqueous solubility of drugs is a major limiting factor with many new drugs in their successful launch in market in spite of their potential pharmacokinetic activity. Poorly water soluble drugs are becoming a problem in terms of obtaining satisfactory dissolution within the gastro intestinal tract, which is necessary for good bioavailability. Poorly water-soluble drugs are associated with slow drug dissolution followed by slow absorption leading eventually to inadequate and variable bioavailability. Various approaches to overcome the poor aqueous solubility of drugs have been investigated like solid dispersion, spherical agglomeration, nanoparticles, nanosuspensions, nanomorphs, nanocrystals, micronization, polymorphism, co-solvency, pH adjustment, use of surfactants, microemulsion, complexation. In this article, the basic approaches for enhancement of solubility and dissolution of poorly water-soluble drugs have been reviewed with literature-based examples of the formulation options for poorly water-soluble compounds and their practical applications to the industrial practices.