Nanosuspensions have emerged as a promising strategy to address the bioavailability challenges of hydrophobic drugs, particularly those with poor solubility in both aqueous and organic environments. This article provides a comprehensive overview of nanosuspensions for topical applications, including ocular, pulmonary, and dermal usage. Nanosuspensions offer several advantages, such as increased skin adhesiveness, heightened saturation solubility, and dissolution rates, which enhance cutaneous distribution. The preparation methods for nanosuspensions include high-pressure homogenization, media milling, and the smart crystal method. The stability and efficacy of nanosuspensions are influenced by factors such as stabilizers, organic solvents, co-surfactants, and other additives. Post-production processing techniques like lyophilization and spray drying are also discussed. The article highlights the importance of evaluating parameters such as particle size, zeta potential, crystal morphology, solubility, dissolution rate, density, pH value, droplet size, viscosity, and physical stability. Additionally, it explores the biological performance of nanosuspensions, including their in vitro/in vivo correlation and surface characteristics. The topical applications of nanosuspensions are detailed, with a focus on ocular, pulmonary, and dermal uses. The article concludes by discussing the challenges and limitations of nanosuspensions, including toxicity hazards and regulatory considerations, and outlines future perspectives and research directions in the field.Nanosuspensions have emerged as a promising strategy to address the bioavailability challenges of hydrophobic drugs, particularly those with poor solubility in both aqueous and organic environments. This article provides a comprehensive overview of nanosuspensions for topical applications, including ocular, pulmonary, and dermal usage. Nanosuspensions offer several advantages, such as increased skin adhesiveness, heightened saturation solubility, and dissolution rates, which enhance cutaneous distribution. The preparation methods for nanosuspensions include high-pressure homogenization, media milling, and the smart crystal method. The stability and efficacy of nanosuspensions are influenced by factors such as stabilizers, organic solvents, co-surfactants, and other additives. Post-production processing techniques like lyophilization and spray drying are also discussed. The article highlights the importance of evaluating parameters such as particle size, zeta potential, crystal morphology, solubility, dissolution rate, density, pH value, droplet size, viscosity, and physical stability. Additionally, it explores the biological performance of nanosuspensions, including their in vitro/in vivo correlation and surface characteristics. The topical applications of nanosuspensions are detailed, with a focus on ocular, pulmonary, and dermal uses. The article concludes by discussing the challenges and limitations of nanosuspensions, including toxicity hazards and regulatory considerations, and outlines future perspectives and research directions in the field.