Polyvinylpyrrolidone

Polyvinylpyrrolidone (PVP), also known as polyvidone or povidone in its branded forms, is a water-soluble synthetic polymer derived from N-vinylpyrrolidone. The polymer consists of repeating pyrrolidone units and is available in a range of molecular weights, commonly referred to by K-values such as K-12, K-30, and K-90. In solution, PVP is non-ionic, highly polar, and forms clear, viscous liquids; when complexed with iodine, it yields povidone-iodine, a widely used antiseptic.

PVP is typically a white to cream-colored powder or resin and is soluble in water and many organic solvents. It is hygroscopic and film-forming, with good adhesive and binding properties. Its chemical inertness and biocompatibility make it a versatile excipient.

In pharmaceutical manufacturing, PVP serves as a binder and filler in tablets and granules, a stabilizer for suspensions, and a film-forming coating. It is also used as a thickener or stabilizer in cosmetics, personal care products, and industrial applications. PVP-based formulations are found in artificial tears and other ophthalmic preparations, where it acts as a viscosity-enhancer. Povidone-iodine, the antiseptic, is created by complexing PVP with molecular iodine.

Overall, PVP is generally regarded as safe for many uses, with low intrinsic toxicity. High molecular weight forms may irritate sensitive tissues, and inhalation of powder should be avoided. It is not readily biodegradable and is excreted largely unchanged in urine after ingestion.