Naphazoline+Hydrochloride

Naphazoline is a vasoconstrictor with a rapid action in reducing swelling when applied to mucous membranes. Naphazoline is the active ingredient in many over the counter eye drops including Clear Eyes.



Warnings and contraindications
A few warnings and [|contraindications] that apply to all naphazoline-containing substances intended for medicinal use are: A possible association with stroke has been suggested. [|[2]]
 * Hypersensitivity to naphazoline
 * Patients taking [|MAO inhibitors] can experience a severe [|hypertensive] crisis if given a [|sympathomimetic] drug such as naphazoline HCl
 * Use in infants and children can result in [|central nervous system] depression, leading to coma and marked reduction in [|body temperature]
 * Should be used with caution in patients with severe [|cardiovascular disease] including [|cardiac arrythmia] and in patients with [|diabetes], especially those with a tendency toward diabetic [|ketoacidosis]
 * Drug interactions can occur with [|anaesthetics] that sensitize the [|myocardium] to sympathomimetics (e.g. [|cyclopropane] or [|halothane] cautiously)
 * Exercise caution when applying prior to use of [|phenylephrine].
 * Extended use may cause [|rhinitis medicamentosa], a condition of [|rebound] [|nasal congestion].

Chemistry
Naphazoline, 2-(1-naphthylmethyl)-2-imidazoline, is synthesized from (1-naphthyl)acetonitrile, which upon reaction with [|ethanol] transforms into iminoester, and undergoes further heterocyclization into the desired [|imidazoline] derivative upon reaction with [|ethylene diamine]