Beta blockers that are non-cardioselective should be avoided in patients with which condition?

Non-cardioselective beta blockers are known to block both beta-1 and beta-2 adrenergic receptors in the body. Beta-1 receptors predominantly affect the heart, while beta-2 receptors are found in various tissues, including the lungs, where they play a critical role in bronchodilation. In patients with asthma, the blockade of beta-2 receptors by non-cardioselective beta blockers can lead to bronchoconstriction, exacerbating respiratory symptoms and potentially triggering an asthma attack.

This is particularly concerning for asthma patients who already have compromised airway function. Therefore, the use of non-cardioselective beta blockers is generally avoided in this population to prevent adverse respiratory effects and to maintain optimal lung function.

Choosing a beta blocker that is cardioselective, which selectively targets beta-1 receptors, would be a safer option for individuals with asthma, as it would minimize the risk of bronchoconstriction while still providing the desired cardiovascular effects.