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 [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). 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 T(30). 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.