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A Computerized Test Battery to Study Pharmacodynamic Effects on the Central Nervous System of Cholinergic Drugs in Early Phase Drug Development
Published on: February 11, 2019
Course and therapy of intoxication with imidazoline derivate naphazoline
1Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany. swenzel@uke.uni-hamburg.de
Objective:
Imidazoline derivatives like naphazoline have a firm place in diagnostics and therapy of otorhinolaryngology because of their vasoconstrictive and decongestive properties. Their alpha-adrenergic potential could induce not only local but also systemic side effects like hypertension and tachycardia which can increase a life-threatening intoxication. Signs of imidazoline intoxication are excessive systolic and diastolic hypertension and hypotension, bradycardia with arrhythmia, respiratory depression, excitation or severe CNS depression.
Patients:
The typical course of an intoxication and its sufficient therapy is reported by means of two cases of intraoperative application of naphazoline for hemostasis.
Results:
In case of overdosage or intoxication, symptomatic drug therapy with intravenous administration of 5 mg phentolamine for adults and 1 mg phentolamine for infants has to be done. Phentolamine, an alpha-adrenoceptor antagonist, acting against peripheral and central side effects has to be used because no specific antidote is available.
Conclusions:
Especially pediatric otorhinolaryngologists have to know about symptoms and therapy of an intoxication after application of naphazoline. Particularly with children, a narrow therapeutic to toxic window can be observed in this frequently used drug.
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