US EPA

2250573 

Journal Article 

Stability of nitroglycerin in intravenous admixtures 

Klamerus, KJ; Ueda, CT; Newton, DW 

1984 

Yes 

American Journal of Hospital Pharmacy
ISSN: 0002-9289 

IPA/84/575169 

J 

REF 7 

303-305 

eng 

IPA COPYRIGHT: ASHP The stability of nitroglycerin (I) in IV admixtures, containing each of 7 injectable drugs (aminophylline, bretylium tosylate, dopamine hydrochloride, furosemide, hydralazine hydrochloride, lidocaine hydrochloride, phentyoin sodium), was studied. Admixtures containing 400 mg/ml of I and each of the 7 injectable drugs in concentrations used clinically were prepared in triplicate in 5% dextrose and 0.9% sodium chloride injections and stored at room temperature for a total of 48 h. At 0, 24, and 48 h, samples of each admixture were assayed by high performance LC for I concentration. The pH of one randomly chosen bottle of each admixture was measured at 0, 24 and 48 h. A significant loss (9%) of I potency at 48 h was observed only in admixtures containing phenytoin (II). Phenytoin crystallization was present in all II admixtures by 24 h. No significant differences in the pH values of any admixture samples assayed at 24 and 48 h were noted; however, admixtures containing II had the most alkaline pH values. It was concluded that, under the conditions studied, I concentrations remained above 90% of the initial values for 48 h in all tested admixtures; however, phenytoin II crystallization limits the stability of II admixtures.