Which group of medications requires monitoring blood pressure closely?

Decongestants are known to cause vasoconstriction, which can lead to an increase in blood pressure. This effect occurs because many decongestants, particularly those containing pseudoephedrine and phenylephrine, stimulate alpha-adrenergic receptors, resulting in narrowing of the blood vessels. As a result, the heart has to work harder to pump blood through these constricted vessels, potentially raising blood pressure.

For patients with hypertension or those at risk of developing high blood pressure, this increase can pose significant health risks. Therefore, it's crucial to monitor blood pressure closely when patients are using decongestants, especially over extended periods or in higher dosages. In contrast, expectorants, antitussives, and antihistamines do not have the same direct impact on blood pressure and therefore do not typically require the same level of monitoring in this regard.