The primary mechanism of action for decongestants involves the stimulation of alpha-adrenergic receptors. This receptor activation leads to vasoconstriction, or the narrowing of blood vessels. By reducing blood flow to the nasal mucosa, decongestants decrease swelling and mucous formation, thereby easing breathing. However, this mechanism also highlights why decongestants need to be used cautiously, especially in individuals with hypertension or cardiovascular issues.
