Overview
Decongestants Reduce Swelling, Not the Cause
A blocked nose is usually narrowed by swollen mucosa, not by an excessive amount of tissue inside the nasal passage.
A blocked nose is usually narrowed by swollen mucosa, not by an excessive amount of tissue inside the nasal passage. Decongestants activate alpha-adrenergic receptors on nasal mucosal blood vessels. Vasoconstriction reduces blood pooling in the venous sinusoids and lowers mucosal edema, so airflow improves. That effect is temporary and narrow in purpose. A decongestant does not eradicate a virus, treat bacterial infection, suppress the allergic inflammatory response, or correct a structural obstruction such as a deviated septum. The nurse should therefore ask two questions: “What is causing the congestion?” and “Is the medication improving airflow without creating a larger systemic problem?” Oral agents such as pseudoephedrine produce a systemic sympathomimetic effect. The same adrenergic stimulation that constricts nasal vessels can increase heart rate, raise blood pressure, cause tremulousness, and interfere with sleep. Topical agents such as oxymetazoline and xylometazoline act directly on nasal tissue, but local application does not eliminate systemic absorption or medication-related risk.