ATC Group: S01GA Sympathomimetics used as decongestants

Brimonidine is an alpha₂-adrenergic receptor agonist that is 1000-fold more selective for the alpha₂-adrenoceptor than the alpha₁-adrenoreceptor. This selectivity results in no mydriasis and the absence of vasoconstriction in microvessels associated with human retinal xenografts.

Naphazoline is a sympathomimetic amine with pronounced alpha adrenergic activity and as a consequence has vasoconstrictor activity.

Oximetazoline is an imidazoline derivative. It exhibits sympathomimetic activity and specifically stimulates the α-adrenergic receptors of the sympathetic system. When administered topically to the nose it causes vasoconstriction of the expansed arterioles of the mucosal nose and a concurrent reduction in blood flow. It also reduces the hypersecretion of the nasal mucosa, ultimately contributing to the decongestion of the nasal mucosa.

Phenylephrine is a sympathomimetic agent with mainly direct effects on adrenergic receptors. It has predominantly alpha adrenergic activity and is without stimulating effects on the central nervous system. The sympathomimetic effect of phenylephrine produces vasoconstriction which in turn relieves nasal congestion.

Tetryzoline is an alpha adrenergic receptor agonist, which is used in form of nasal solution or spray for decongestion of nasal and nasopharyngeal mucosa.

Xylometazoline acts directly on α-adrenoreceptors but does not act on β-receptors. When used topically as a nasal decongestant, xylometazoline acts rapidly and provides long-lasting relief. Onset of action is within minutes, the decongestant effect being prolonged and lasting for up to 10 hours.