β-Cyclodextrin and its derivatives are widely used in tablets, capsules, oral solutions and suspensions, injectables, topical dermatological preparations, ophthalmic preparations, and other dosage forms including suppositories, aerosols, transdermal patches and nanoparticles. It is a cyclic oligosaccharide composed of seven glucose units linked by α-1,4-glycosidic bonds, featuring a hydrophilic outer surface and a hydrophobic inner cavity with a diameter of approximately 6–6.5 ?. This substance encapsulates poorly soluble drug molecules within its hydrophobic cavity via hydrophobic interactions (such as van der Waals forces), forming inclusion complexes. The surface of the inclusion complex is covered by the hydrophilic shell of the cyclodextrin, thereby significantly improving the apparent solubility, stability and bioavailability of the drug, whilst also achieving effects such as controlled release, masking of taste, and reduction of irritation and toxicity.