Rarely, paradoxical bronchospasm may occur with use of inhaled bronchodilating agents. Immediate hypersensitivity reactions (urticaria, angioedema, rash, bronchospasm) reported. Serious adverse events, including fatalities, associated with excessive use of inhaled sympathomimetics. Do not use as a component of chronic therapy without an anti-inflammatory agent. Use with caution in cardiovascular disease (arrhythmia or hypertension or HF); β-agonists may cause elevation in blood pressure, heart rate and result in CNS stimulation/excitation. β~2~-agonists may also increase risk of arrhythmias. Use with caution in diabetes mellitus (β~2~-agonists may increase serum glucose), in glaucoma (may elevate intraocular pressure), in hyperthyroidism (may stimulate thyroid activity), in hypokalemia (β~2~-agonists may decrease serum potassium), and in seizure disorders (β-agonists may result in CNS stimulation/excitation). When used for tocolysis, there is some risk of maternal pulmonary edema (associated with the following risk factors: excessive hydration, multiple gestation, occult sepsis and underlying cardiac disease).