Which medication is often used for immediate relief of an anginal attack?

Nitroglycerin is frequently used for the immediate relief of an anginal attack due to its rapid onset of action as a vasodilator. When administered, nitroglycerin works by relaxing the smooth muscles in the blood vessels, primarily leading to dilation of the coronary arteries, which increases blood flow to the heart muscle. This alleviates the chest pain associated with angina by reducing myocardial oxygen demand and improving oxygen delivery.

In situations where chest pain occurs suddenly—indicative of an anginal attack—nitroglycerin can be given sublingually, allowing it to be absorbed quickly into the bloodstream for prompt relief. This characteristic makes it a first-line treatment during acute episodes of angina.

Calcium channel blockers, beta-blockers, and ACE inhibitors can be utilized for managing chronic angina and can help prevent anginal attacks over the long term. However, they are not designed for immediate relief of acute episodes. Instead, they work by various mechanisms to lower heart rate, decrease myocardial oxygen demand, and manage blood pressure, but their onset of action isn't as swift as that of nitroglycerin, making them less suitable for emergency situations.