Side effects associated with all β-adrenergic
agonists are largely due to sympathomimetic effects and include
tremors, anxiety, nausea, headache, vomiting, tachycardia, arrhythmia,
hypertension, and hypotension. Nonsympathomimetic side effects include decreased
oxygen saturation (secondary to altered V/Q matching),
which is common, and paradoxical bronchospasm, which is rare. Metabolic
side effects include hypokalemia, hypophosphotemia, hyperglycemia,
and lactic acidosis. These side effects are often related to dose
and route of administration and rarely require cessation of therapy.
However, all patients receiving prolonged β-adrenergic
therapy should have their oxygen saturation, heart rate, blood pressure,
and serum electrolytes monitored closely.