Other β-adrenergics, anticholinergics and xanthine derivatives (eg, theophylline) may enhance the bronchodilatory effect. The concurrent administration of other β-mimetics, systemically available anticholinergics and xanthine derivatives (eg, theophylline) may increase the adverse reactions.
A potentially serious reduction in bronchodilation may occur during concurrent administration of β-blockers.
Beta-agonist-induced hypokalemia may be increased by concomitant treatment with xanthine derivatives, corticosteroids and diuretics. This should be taken into account particularly in patients with severe airway obstruction.
Hypokalemia may result in an increased susceptibility to arrhythmias in patients receiving digoxin. Additionally, hypoxia may aggravate the effects of hypokalemia on cardiac rhythm. It is recommended that serum potassium levels are monitored in such situations.
Beta2-agonists containing medicinal products should be administered with caution to patients being treated with monoamine oxidase inhibitors or tricyclic antidepressants, since the action of β-adrenergic agonists may be enhanced.
Inhalation of halogenated hydrocarbon anesthetics eg, halothane, trichloroethylene and enflurane may increase the susceptibility on the cardiovascular effects of β-agonists.