Sympathomimetics oxymetazoline

Oxymetazoline. Is a sympathomimetic (this is much like psychotomimetic), orally active at 5 to 10 mg per kilogram of body weight. 

Indirectly acting sympathomimetics include dexamfetamine, ephedrine (mixed), isometheptene, methylphenidate, oxymetazoline, phenylpropanolamine (mixed), pseudoephedrine (mixed) and xylometazoline. 

The development of an acute retinal artery obstruction in a young, otherwise healthy man was associated with excessive use of an oxymetazoline nasal spray. Platelet coagulation studies indicated a platelet aggregation hypersensitivity to adenosine diphosphate and adrenaline. Predisposition to sympathomimetic drug-induced platelet fibrin embolus formation may have played a role in this case (2). 

A few important compounds used as sympathomimetic drugs are discussed below ephedrine epinephrine adrenaline isoprenaline methoxamine hydrochloride metarminol bitartrate naphazoline hydrochloride oxymetazoline hydrochloride phenylpropanolamine hydrochloride xylometazoline hydrochloride, etc. 

The clinic nurse is discussing over-the-counter (OTC) oxymetazoline (Afrin 12 Hour Nasal Spray), a sympathomimetic, with a client experiencing nasal congestion. 

An investigation of the vasoconstrictor activity of substituted imidazolines by Fritz Uhlmann at Ciba in Basle, Switzerland during the early 1940 s resulted in the introduction of the sympathomimetic drug, naphazoline its analogs, xylometazoline and oxymetazoline, used as decongestants and... 

A water soluble form of the active substance is preferred. This may bring about oxidation or hydrolysis reactions (see Sect. 22.2). Common sympathomimetics such as naphazoline, oxymetazoline and xylometazoline may hydrolyse in aqueous solution, but this happens only at a pH higher than what is normal for nasal preparations, or at a higher temperature than what is normal for the storage of these preparations. 

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