Symptoms: Turbuhaler/Injection: Too frequent administration, as with other sympathomimetic agents, may cause nausea, headaches, changes in blood pressure, anxiety, tension, restlessness, insomnia, tremor, excitement, tonic muscle cramps, palpitations, tachycardia and cardiac arrhythmias. The symptoms and signs are those characteristic of excessive sympathetic stimulation.
Laboratory Findings: Hyperglycaemia and lactacidosis sometimes occur. β2-agonists may cause hypokalaemia as a result of redistribution of potassium, but this usually requires no treatment.
Treatment: Metabolic changes should be corrected. The preferred antidote for overdosage with Bricanyl is a cardioselective β-adrenergic-blocking agent eg, metoprolol (5-10 mg by slow IV injection, repeated if necessary after 5 min). β-blockers should be used with caution in patients with a history of bronchospasm because of the possibility of inducing bronchial obstruction. If the β2-mediated reduction in peripheral vascular resistance significantly contributes to the fall in blood pressure, a volume expander should be given.