Why beta-blockers are contraindicated in vasospastic angina?

Beta-blockers are contraindicated in vasospastic angina because they can exacerbate vasospasm by blocking beta-2 adrenergic receptors, which normally mediate vasodilation. In patients with vasospastic angina, the primary issue is inappropriate vasoconstriction, and using beta-blockers may worsen this condition by limiting the body's ability to dilate blood vessels during episodes of angina. Instead, calcium channel blockers or nitrates are preferred as they promote vasodilation and help alleviate symptoms.