A drug that decreases mucus in the nasal passages is called a(n) ____________.

A drug that decreases mucus in the nasal passages is referred to as a decongestant. Decongestants work by narrowing the blood vessels in the nasal passages, which decreases swelling and congestion. This action helps to clear nasal passages and allow for easier breathing by reducing mucus production and facilitating drainage.

Expectorants, on the other hand, are designed to increase mucus secretion in order to help clear mucus from the respiratory tract, which is the opposite effect of what is intended for nasal congestion. Antitussives are cough suppressants that primarily reduce the cough reflex but do not necessarily affect mucus levels. Antipyretics are medications that reduce fever and are not related to mucus production in the nasal passages. Therefore, decongestants are specifically indicated for the purpose of reducing mucus and alleviating nasal congestion.