Snapshot A 22-year-old woman presents to the emergency department with shortness of breath. She has a history of seasonal allergies and eczema. The patient is tachypneic but is saturating well on room air. Physical exam is notable for bilateral wheezes and poor air movement. The patient is given albuterol and her wheezing decreases and she feels better. (Asthma) introduction One of 7 medications used for asthma aimed to reduce inflammation and obstruction corticosteroids β-agonists muscarinic antagonists methylxanthines antileukotrienes omalizumab Introduction Drugs short-acting, may be used during acute exacerbation albuterol and levalbuterol (β2) login to view 2 more bullets terbutaline (β2) login to view 2 more bullets metaproterenol (β2 and minor β1) login to view 1 more bullet long-acting, prophylaxis only salmeterol and formoterol (β2) login to view 1 more bullet Mechanism of action β-2 agonism increases cAMP causing smooth muscle relaxation improving air flow tachycardia when acting on the heart vasodilation when acting on the blood vessels tremor, sweating, anxiety, and agitation when acting systemically intracellular sequestration of potassium β-1 agonism increases cAMP causing the following undesirable side effects cardiac effects login to view 4 more bullets Clinical use asthma COPD bronchospasm from chemical irritation hyperkalemia Adverse effects could be harmful in bronchiolitis tachycardia hypokalemia can cause U-waves on ECG anxiety