Which of the following is an adverse effects of beta-2-agonist?
**Core Concept**
Beta-2-agonists are a class of medications that act as adrenergic receptor agonists, specifically targeting the beta-2 adrenergic receptors found in the smooth muscle of the airways, leading to bronchodilation. This mechanism is exploited in the treatment of asthma and chronic obstructive pulmonary disease (COPD).
**Why the Correct Answer is Right**
The adverse effect of beta-2-agonists is related to their action on beta-2 receptors, which can lead to hypokalemia (decreased potassium levels). This occurs due to the inhibition of potassium efflux from the cells by beta-2 agonism. Additionally, beta-2 agonists can cause a shift from type 1 to type 2 fibers in the airway smooth muscle, leading to a decrease in the sensitivity to beta-2 agonists over time. Furthermore, beta-2 agonists can also cause tachycardia and tremors, but these are not the most significant adverse effects associated with this class of medications.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not a known adverse effect of beta-2 agonists. Beta-2 agonists do not typically cause hyperglycemia as an adverse effect.
**Option B:** This option is not a correct adverse effect of beta-2 agonists. Beta-2 agonists can cause tachycardia, but this is not the most significant adverse effect associated with this class of medications.
**Option D:** This option is not a correct adverse effect of beta-2 agonists. Beta-2 agonists can cause tremors, but this is not the most significant adverse effect associated with this class of medications.
**Clinical Pearl / High-Yield Fact**
Beta-2 agonists can cause a paradoxical bronchospasm in some patients, which can be a life-threatening condition. This is often referred to as beta-2 agonist-induced bronchospasm.
**Correct Answer: A. Hypokalemia.**