tetryzoline
(tetrahydrozoline)
Alpha-1 agonist.
It is used in some over-the-counter eye drops and nasal sprays.
It is not suitable for prolonged use, because it can cause opposite effects as rebound effect (developed tolerance).
It can be combined in a solution with antazoline, which is a 1st generation antihistamine (histamine H1 receptor antagonist with anticholinergic properties) used for the symptomatic treatment of nasal congestion and allergic conjunctivitis.
(Indications)
• redness of the eye
• allergic conjunctivitis
• allergic rhinitis
• nasal congestion
(Side effects)
As eye drops:
• blurred vision
• eye irritation
• dilated pupils
As nasal sprays:
• transient burning, stinging, or dryness of the mucosa
• sneezing
In children:
• profound sedation
(Overdose)
It often occurs in children.
• bradycardia
• respiratory depression
• hypotension
• miosis (constricted pupils)
• hypothermia
• brief episodes of hypertension
• drowsiness
• headaches
• vomiting
• circulatory shock (in serious cases)