Chemical and Physical Compatibility of Levalbuterol Inhalation Solution Concentrate Mixed With Budesonide, Ipratropium Bromide, Cromolyn Sodium, or Acetylcysteine Sodium

Medications are frequently combined in the nebulizer cup, so it is important to determine their chemical and physical compatibility. To determine the chemical and physical compatibility of levalbuterol with ipratropium bromide, cromolyn sodium, acetylcysteine sodium, and budesonide. We mixed one dose of levalbuterol inhalation solution concentrate (1.25 mg/0.5 mL) with one dose of ipratropium bromide (0.5 mg/2.5 mL), cromolyn sodium (20 mg/2 mL), acetylcysteine sodium (1,000 mg/5 mL), or budesonide (0.5 mg/2 mL). Immediately after mixing the 2 drugs (time zero [T(0)]), and again after 30 min at room temperature (T(30)), we visually inspected the admixtures, measured their pH, and conducted high-pressure liquid chromatography (HPLC). There was no evidence of physical incompatibility with these drugs combinations. With all the admixtures, both drugs were chemically stable for at least 30-min. Admixture pH had not changed significantly at T(30). Drug recovery was 93.2-102.6% of the initial or control values. The 2-drug admixtures we studied were compatible for at least 30 min at room temperature.