18.6 : 上呼吸道药物：镇咳药、祛痰药和粘液溶解药

Common respiratory discomforts, including congestion and cough, can be relieved using antitussives, expectorants, and mucolytics.

Antitussives, like codeine and dextromethorphan, act centrally and suppress the cough reflex center in the medulla. In contrast, benzonatate acts peripherally on the respiratory tract. Antitussives alleviate nonproductive coughs, providing relief from persistent coughs.

Expectorants, like guaifenesin, enhance respiratory secretion production, reducing mucus viscosity.

This facilitates mucus expulsion from the respiratory passages, aiding conditions characterized by thick, sticky mucus.

Mucolytics, such as acetylcysteine and dornase alfa, break down thick mucus in the lower portions of the lungs, easing elimination.

Acetylcysteine is used to treat pneumonia, bronchitis, and cystic fibrosis.

This drug poses potential side effects, including lightheadedness, dizziness, and drowsiness, especially when combined with an antihistamine.

Antitussives and expectorants warrant caution during pregnancy, lactation, and in asthma patients.

Mucolytics, in general, are not recommended for asthma patients.