Other adrenergic agents may potentiate the sympathetic effects. Long-acting beta-2 agonists should not be coadministered. Short-acting beta-2 agonists should not be taken on a regular basis and should only be used for symptomatic relief of acute asthma symptoms.
Beta-blockers block the therapeutic effects of beta-2 agonists and may produce bronchospasm in patients with asthma and COPD. Effects of both agents may be inhibited. In these patients, a cardioselective beta-blocker should be considered; although, they should be administered with caution.
Drugs known to prolong the QTc interval, MAOIs, tricyclic antidepressants
Formoterol may potentiate the CV effects of these agents, increasing the risk of cardiac arrhythmia. Use with extreme caution.
Coadministration of linezolid and formoterol may result in adverse CV effects characterized by hypertension. Caution should be used with or within 2 wk of coadministration of linezolid and formoterol. Monitor BP.
Methylxanthines (eg, aminophylline, theophylline)
Concomitant treatment with methylxanthines may potentiate the hypokalemic effects of formoterol. In addition, concurrent use of theophyllines and formoterol may augment the bronchodilating response. Measure theophylline concentrations and adjust the theophylline dose as needed. Monitor serum potassium.