title: The use of hypromellose in oral drug delivery.
abstract: Hypromellose, formerly known as hydroxypropylmethylcellulose (HPMC), is by far the most commonly employed cellulose ether used in the fabrication of hydrophilic matrices. Hypromellose provides the release of a drug in a controlled manner, effectively increasing the duration of release of a drug to prolong its therapeutic effect. This review provides a current insight into hypromellose and its applicability to hydrophilic matrices in order to highlight the basic parameters that affect its performance. Topics covered include the chemical, thermal and mechanical properties of hypromellose, hydration of the polymer matrices, the mechanism of drug release and the influence of tablet geometry on drug-release rate. The inclusion of drug-release modifiers within hypromellose matrices, the effects of dissolution media and the influence of both the external environment and microenvironment pH within the gel matrix on the properties of the polymer are also discussed.
authors.affiliation: GlaxoSmithKline Pharmaceuticals, Pharmaceutical Development, New Frontiers Science Park South, Third Avenue, Harlow, Essex, CM19 5AW, UK.
authors.forename: Chi L
authors.initials: CL
authors.lastname: Li
authors.forename: Luigi G
authors.initials: LG
authors.lastname: Martini
authors.forename: James L
authors.initials: JL
authors.lastname: Ford
authors.forename: Matthew
authors.initials: M
authors.lastname: Roberts
mesh_terms: D000284:Administration, Oral; D002214:Capsules; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry*; D004355:Drug Stability; D065347:Hypromellose Derivatives; D008747:Methylcellulose / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry*; D010316:Particle Size; D012995:Solubility; D013718:Tensile Strength; D014783:Viscosity
chemical_list: D002214:Capsules; D004337:Drug Carriers; D065347:Hypromellose Derivatives; D008747:Methylcellulose