A drug that causes dilation of blood vessels is called a __________.

A drug that causes dilation of blood vessels is referred to as a vasodilator. This type of medication works by relaxing the smooth muscle in the blood vessel walls, which leads to an increase in the diameter of the blood vessels. This process reduces blood pressure and increases blood flow to various tissues and organs, making vasodilators useful in treating conditions such as hypertension and angina.

In contrast, antipyretics are drugs used to reduce fever, diuretics increase urine production to help reduce fluid overload, and appetite suppressants are designed to decrease hunger and aid in weight loss. While all these drugs serve important roles in various medical contexts, they do not influence blood vessel dilation directly, distinguishing the vasodilator as the correct answer to the question.