A review on solubility enhancement methods for poorly water-soluble drugs

One of the most important parameters in pharmacy is drug solubility. Solubility affects the efficacy of a drug. Drug solubility has an important role in determining the concentration of a drug to achieve the necessary pharmacological response, as all drugs absorbed by the body must be in the form of a solution. Drug solubility is quite a common issue and affects the bioavailability of a drug in the body. Drugs with low solubility are poorly absorbed, resulting in poor bioavailability. Many methods have been developed for increasing the solubility of a drug. In this review, we will describe possible efforts for improving the solubility of a drug, e.g., reducing particle size, surfactants, the use of nanosuspension technology, solid dispersion, salt formation, pH adjustment, hydrotropy, cocrystal, amorphous compound formation, and inclusion complexes. The main objective of this review was to focus on efforts that can increase the solubility of a drug to obtain good drug efficacy.