Xylometazoline Hydrochloride

Nasal congestion arises from several causes, including rhinosinusitis and allergic or non-allergic rhinitis, all of which lead to swelling of the venous sinusoids that line the nasal mucosa. Activating alpha adrenergic receptors constricts the blood vessels of the nasal mucosa and restores nasal airflow. Because alpha1A and alpha2B adrenoceptors are the most abundant in the human nasal mucosa, they likely play the greatest role in this constriction. Xylometazoline acts as a more selective agonist at alpha2B adrenoceptors, while also showing affinity for alpha1A, alpha2A, alpha2C, alpha1B, and alpha1D adrenoceptors. It reduces nasal resistance during both inspiration and expiration and increases nasal airflow volume. Compared with oxymetazoline, another imidazoline nasal decongestant, xylometazoline tends to act slightly faster, though the two have a similar duration of effect. One study found that people with nasal congestion also experienced relief from earache and sore throat after using the medication, in addition to nasal decongestion. Researchers speculate that oxymetazoline produces this effect by constricting the blood vessels of the nasal mucosa, which contains the venous sinuses; the resulting decongestion allows breathing through the nose again, easing the sore throat that mouth breathing causes by drying and irritating the throat.