title: Diamorphine stability in aqueous solution for subcutaneous infusion.
abstract: The influence of temperature and concentration on diamorphine stability during storage over 8 weeks has been investigated. Ampoules containing diamorphine hydrochloride in concentrations from 0.98-250 mg mL-1 have been stored at -20, 4, 21 and 37 degrees C for 8 weeks. Their content of diamorphine, 6-monoacetylmorphine and morphine, on measurement by high performance liquid chromatography after 1, 2, 4, 6 and 8 weeks storage changed to slow degradation of diamorphine at all concentrations at temperatures of 4 degrees C and above. This was accompanied by a corresponding increase in 6-monoacetylmorphine and morphine. There was an associated fall in pH and development of a strong odour characteristic of acetic acid. Precipitation and a white turbidity seen in solutions of 15.6 mg mL-1 and above, appeared after 2 weeks incubation.
authors.affiliation: Department of Clinical Pharmacology, St. Bartholomew's Hospital, London, UK.
authors.forename: O A
authors.initials: OA
authors.lastname: Omar
authors.forename: P J
authors.initials: PJ
authors.lastname: Hoskin
authors.forename: A
authors.initials: A
authors.lastname: Johnston
authors.forename: G W
authors.initials: GW
authors.lastname: Hanks
authors.forename: P
authors.initials: P
authors.lastname: Turner
mesh_terms: D004355:Drug Stability; D003932:Heroin / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D009020:Morphine / Q000032:analysis; D009022:Morphine Derivatives / Q000032:analysis; D012996:Solutions; D013696:Temperature
chemical_list: D009022:Morphine Derivatives; D012996:Solutions; D003932:Heroin; D009020:Morphine; C026979:6-O-monoacetylmorphine