The vast majority of<unk> s act via enhancing norepinephrine (noradrenaline) and epinephrine (adrenaline) or adrenergic activity by stimulating the α1-adrenergic receptor since they mediate vasoconstriction and constricting nasal vasculature causes decongestion of nasal mucosa. This induces vasoconstriction of the blood vessels in the nose, throat, and paranasal sinuses, which results in reduced inflammation (swelling) and mucus formation in these areas.<unk>  nasal sprays and eye drops often contain oxymetazoline and are used for topical decongestion. Pseudoephedrine acts indirectly on the adrenergic receptor system, whereas phenylephrine and oxymetazoline are direct agonists. The effects are not limited to the nose, and these medicines may cause hypertension (high blood pressure) through vasoconstriction; it is for this reason that people with hypertension are advised to avoid them. Most<unk> s, however, are not pronounced stimulants, due to lack of response from the other adrenoreceptors. Besides hypertension, common side-effects include sleeplessness, anxiety, dizziness, excitability, and nervousness. Topical nasal or ophthalmic<unk> s quickly develop tachyphylaxis (a rapid decrease in the response to a drug after repeated doses over a short period of time). Long-term use is not recommended since these agents lose effectiveness after a few days.
Decongestant
Anticoagulant
Cholagogue
Antipyretic
Antiemetic
Antidote
Antiplatelet drug
Lipid-lowering agent