What is a significant side effect associated with α1 antagonists?

The significant side effect associated with α1 antagonists is orthostatic hypotension. α1 antagonists work by blocking α1-adrenergic receptors, which results in vasodilation and a decrease in blood pressure. When a person takes these medications, especially when standing up quickly, there may be an inadequate compensatory response in blood vessel constriction leading to a sudden drop in blood pressure. This can cause dizziness, lightheadedness, or even fainting upon standing, a condition known as orthostatic hypotension.

The other side effects mentioned, such as bradycardia, rash, and high blood sugar, are not typically associated with α1 antagonists. Instead, bradycardia is more commonly linked with β-blockers, while rash and high blood sugar can be side effects of various other medications but are not significant concerns for α1 antagonists specifically. Understanding these specific effects is crucial for managing patient care effectively.