Bambuterol prolongs the muscle-relaxing effect of suxamethonium (succinylcholine). This is due to the fact that plasma cholinesterase, which inactivates suxamethonium, is partly inhibited by bambuterol. The inhibition is dose-dependent and fully reversible after cessation of treatment with bambuterol. This interaction should also be considered with other muscle relaxants which are metabolized by plasma cholinesterase.
Beta-receptor blocking agents (including eye-drops), especially those which are non-selective, may partly or totally inhibit the effect of beta-stimulants.
Halogenated anaesthetics: Halothane anaesthesia should be avoided during β2-agonists treatment, since it increases the risk of cardiac arrhythmias. Other halogenated anesthetics should be used cautiously together with β2-agonists.
Potassium depleting agents and hypokalaemia: Owing to the hypokalaemic effect of beta agonists, concurrent administration of serum potassium depleting agents known to exacerbate the risk of hypokalaemia, such as diuretics, methyl xanthines and corticosteroids, should be administered cautiously after careful evaluation of the benefits and risks with special regard to the increased risk of cardiac arrhythmias arising as a result of hypokalaemia (see Precautions). Hypokalaemia also predisposes to digoxin toxicity.