What is a common side effect of sublingual nitroglycerin?

Sublingual nitroglycerin is commonly used for the acute relief of angina pectoris due to its rapid onset of action. A well-recognized side effect of this medication is the occurrence of headache and flushing. This happens because nitroglycerin acts as a vasodilator, leading to the relaxation of blood vessels, which can result in decreased blood flow to certain areas and an increase in blood flow to others, like the face, causing flushing. The headache is often attributed to the vasodilation as well, affecting cerebral blood vessels.

While other side effects can occur with various medications, headache and flushing are particularly associated with the use of nitroglycerin and reflect the drug's pharmacological effects on the vascular system. This characteristic helps healthcare providers anticipate potential responses when administering this medication.