What is a common side effect of bronchodilator medications?

Bronchodilator medications, commonly used to treat conditions like asthma and chronic obstructive pulmonary disease (COPD), work by relaxing the muscles around the airways and making it easier to breathe. One of the notable side effects of these medications, especially the beta-agonists, is increased heart rate or tachycardia. This occurs because these medications stimulate the sympathetic nervous system, leading to increased heart contractility and heart rate as they activate beta-adrenergic receptors, particularly beta-1 receptors in the heart.

While other side effects may occur with bronchodilators, such as dry mouth or skin rash, these are not as commonly associated with bronchodilator use as tachycardia. Weight gain is also not a recognized side effect of bronchodilators; instead, weight loss might be seen in patients with respiratory conditions who experience improved airflow and exercise capacity after using these medications. Therefore, increased heart rate stands out as a typical and expected side effect of bronchodilator therapy.