ATC Group: R01AA Sympathomimetics, plain

Ephedrine is a sympathomimetic amine acting directly on the alpha and beta receptors and indirectly by increasing the release of noradrenaline by the sympathetic nerve endings. As with any sympathomimetic agent, ephedrine stimulates the central nervous system, the cardiovascular system, the respiratory system, and the sphincters of the digestive and urinary systems.

Epinephrine is a direct acting sympathomimetic agent, which exerts effects on both α and β adrenoceptors. It has more pronounced effects on β than on α adrenoceptors, although α effects prevail at high doses. The effects of adrenaline include increased rate and force of cardiac contraction, cutaneous vasoconstriction and broncho-dilatation.

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.

Tramazoline is an α-sympathomimetic agent with local action, which mainly causes vasoconstriction and therefore immediately reduces mucosal edema.

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.