The article discusses the impact of nanotechnology on drug delivery and clinical applications, focusing on the development and marketization of drug nanocrystals. Nanocrystals, which are nanoparticles with a size below 1000 nm, have been shown to enhance the solubility and bioavailability of poorly soluble drugs. The article reviews the physics behind the formation of drug nanocrystals and the changes in their physical properties, such as increased surface area and saturation solubility. It also presents several commercially available products that utilize nanocrystal technology, including Rapamune, Emend, Tricor, and Megace ES, highlighting their benefits in terms of improved bioavailability, reduced side effects, and enhanced patient compliance. Additionally, the article outlines the production methods for nanocrystals, including pearl milling, high-pressure homogenization, and precipitation techniques. Finally, it discusses the potential of nanocrystal technology in future drug formulations, particularly for drugs with narrow therapeutic windows and poor solubility.The article discusses the impact of nanotechnology on drug delivery and clinical applications, focusing on the development and marketization of drug nanocrystals. Nanocrystals, which are nanoparticles with a size below 1000 nm, have been shown to enhance the solubility and bioavailability of poorly soluble drugs. The article reviews the physics behind the formation of drug nanocrystals and the changes in their physical properties, such as increased surface area and saturation solubility. It also presents several commercially available products that utilize nanocrystal technology, including Rapamune, Emend, Tricor, and Megace ES, highlighting their benefits in terms of improved bioavailability, reduced side effects, and enhanced patient compliance. Additionally, the article outlines the production methods for nanocrystals, including pearl milling, high-pressure homogenization, and precipitation techniques. Finally, it discusses the potential of nanocrystal technology in future drug formulations, particularly for drugs with narrow therapeutic windows and poor solubility.