Hydroxypropyl methylcellulose (INN name: Hypromellose), also abbreviated as hydroxypropyl methylcellulose (abbreviated as HPMC), is a variety of non-ionic cellulose mixed ethers. It is a semi-synthetic, inactive, viscoelastic polymer commonly used in ophthalmology as a lubricant, or as an excipient or excipient in oral medicines, commonly found in a wide variety of commodities. As a food additive, hydroxypropyl cellulose can serve as emulsifier, thickener, suspension agent and substitute for animal gelatin. Its Codex Code (E code) is E464.