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

BACKGROUND: Medications are frequently combined in the nebulizer cup, so it is important to determine their chemical and physical compatibility.

OBJECTIVE: To determine the chemical and physical compatibility of levalbuterol with ipratropium bromide, cromolyn sodium, acetylcysteine sodium, and budesonide.

METHODS: 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 [T₀]), and again after 30 min at room temperature (T₃₀), we visually inspected the admixtures, measured their pH, and conducted high-pressure liquid chromatography (HPLC)..

RESULTS: 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 T₃₀. Drug recovery was 93.2–102.6% of the initial or control values.

CONCLUSIONS: The 2-drug admixtures we studied were compatible for at least 30 min at room temperature.