title: Stability of Adrenaline in Irrigating Solution for Intraocular Surgery.
abstract: Intraocular irrigating solution containing 1 µg/mL adrenaline is widely used during cataract surgery to maintain pupil dilation. Prepared intraocular irrigating solutions are recommended for use within 6 h. After the irrigating solution is admistered for dilution, the adrenaline may become oxidized, and this may result in a decrease in its biological activity. However, the stability of adrenaline in intraocular irrigating solution is not fully understood. The aim of this study was to evaluate the stability of adrenaline in clinically used irrigating solutions of varying pH. Six hours after mixing, the adrenaline percentages remaining were 90.6%±3.7 (pH 7.2), 91.1%±2.2 (pH 7.5), and 65.2%±2.8 (pH 8.0) of the initial concentration. One hour after mixing, the percentages remaining were 97.6%±2.0 (pH 7.2), 97.4%±2.7 (pH 7.5), and 95.6%±3.3 (pH 8.0). The degradation was especially remarkable and time dependent in the solution at pH 8.0. These results indicate that the concentration of adrenaline is decreased after preparation. Moreover, we investigated the influence of sodium bisulfite on adrenaline stability in irrigating solution. The percentage adrenaline remaining at 6 h after mixing in irrigating solution (pH 8.0) containing sodium bisulfite at 0.5 µg/mL (concentration in irrigating solution) or at 500 µg/mL (concentration in the undiluted adrenaline preparation) were 57.5 and 97.3%, respectively. Therefore, the low concentration of sodium bisulfite in the irrigating solution may be a cause of the adrenaline loss. In conclusion, intraocular irrigation solution with adrenaline should be prepared just prior to its use in surgery.
authors.affiliation: Department of Pharmaceutical Services, Hiroshima University Hospital.
authors.forename: Yuuka
authors.initials: Y
authors.lastname: Shibata
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kimura
authors.forename: Takanori
authors.initials: T
authors.lastname: Taogoshi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Matsuo
authors.forename: Kenji
authors.initials: K
authors.lastname: Kihira
mesh_terms: D004355:Drug Stability; D004837:Epinephrine / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009883:Ophthalmic Solutions / Q000737:chemistry*; D013508:Ophthalmologic Surgical Procedures; D013447:Sulfites / Q000737:chemistry; D013997:Time Factors
chemical_list: D009883:Ophthalmic Solutions; D013447:Sulfites; C009279:sodium bisulfite; D004837:Epinephrine