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|Systematic (IUPAC) name|
|Intranasal spray or drops, oral (capsules)|
|Biological half-life||>10 seconds|
|ATC code||R01 S01|
|Molecular mass||244.37516 g/mol|
|(what is this?)|
Xylometazoline (Pronunciation: Zylow-met-TAH-zoleen), also known as xylomethazoline, is a drug which is used as a topical nasal decongestant. It is applied directly into the nose, either as a spray or as drops.
Xylometazoline is marketed under many brand names (see below) but the most common by far is Otrivine. The standard adult solution strength is 0.1% w/v xylometazoline, and the dose for children under 12 is usually 0.05%. 
It should not be used for too long a period of time, or rebound effect may occur after discontinuation (see: Rhinitis medicamentosa). It is on the World Health Organization's List of Essential Medicines, a list of the most important medication needed in a basic health system.
Mechanism of action
The drug works by constricting the blood vessels in the nose. The decongestant effect is due to constriction of large veins in the nose which swell up during the inflammation of any infection or allergy of the nose. The smaller arteries are also constricted and this causes the colour of the nasal epithelium to be visibly paler after dosage.
Xylometazoline is an imidazole derivative which is designed to mimic the molecular shape of adrenaline. It binds to alpha-adrenergic receptors in the nasal mucosa. Due to its sympathomimetic effects, it should not be used by people with high blood pressure, or other heart problems.
Extended usage of xylometazoline can result in decreased effectiveness or a buildup of tolerance against the drug. The number of receptors decreases, and when the administration of the drug is ceased, chronic congestion can occur; this is called rhinitis medicamentosa, commonly referred to as rebound congestion. Moreover long-term overdosing can cause degenerative changes in nasal mucous membranes that pose another health problem.
Xylometazoline is sold under a number of brand names worldwide, including: Antazol (Square, BD), Xylomet (Opsonin, BD) Cirovin, Klarigen (in Denmark), Nasolin, Neo-Rinoleina, Novorin, Olynth, Otrinoz, Otriven, Otrivin, Otrivine, Otrix, Rhinoset, Nosikind (in India), Naphthyzinium, Xymelyn (in Latvia), Sinutab Nasal Spray, Snup akut, Sudafed, Xylo-COMOD, Xylolin (in UAE), Xylovit, Olynth (in Serbia), Xynosine (in Pakistan, Afghanistan, Kyrgyzstan and Kazakhstan), Xymelin, Zymelin, Xylostar, Xylorin (in Poland), Kompendium (Switzerland), and Decozal (in Jordan).
- Eccles, R.; Eriksson, M.; Garreffa, S.; Chen, S. (2008). "The nasal decongestant effect of xylometazoline in the common cold". American journal of rhinology 22 (5): 491–496. doi:10.2500/ajr.2008.22.3202. PMID 18655753.
- "WHO Model List of EssentialMedicines" (PDF). World Health Organization. October 2013. Retrieved 22 April 2014.
- Haenisch, B.; Walstab, J.; Herberhold, S.; Bootz, F.; Tschaikin, M.; Ramseger, R.; Bönisch, H. (2009). "Alpha-adrenoceptor agonistic activity of oxymetazoline and xylometazoline". Fundamental & clinical pharmacology 24 (6): 729–739. doi:10.1111/j.1472-8206.2009.00805.x. PMID 20030735.
- Gold Standard Clinical Pharmacology