riboflavin + hydroxypropyl methylcellulose

A pharmaceutical combination where hydroxypropyl methylcellulose (HPMC) serves as a polymer excipient and riboflavin (vitamin B2) is the active pharmaceutical ingredient. This combination is primarily used in gastric floating tablets for extended release, ophthalmic preparations, and advanced drug delivery systems. HPMC provides several functional benefits: - Controlled Release Matrix: Forms a gel barrier for sustained drug release - Film Coating: Protects the drug from environmental factors - Bioadhesive Properties: Improves adhesion in drug delivery systems - Thickening and Stabilizing: Enhances viscosity and prevents particle settling This combination offers several advantages: - Extended drug action time - Maintained stable blood drug concentration - Improved bioavailability - Lower toxicity and reduced side effects - In ophthalmic applications, it provides better corneal thickness maintenance