Homatropine Hydrobromide
Mechanism :
Homatropine is a tertiary amine anticholinergic agent used topically to produce mydriasis and cycloplegia. It blocks the responses of the iris sphincter and ciliary muscle to cholinergic stimuli. Homatropine is less potent than atropine and has a shorter duration of action. Complete cycloplegia is not usually attainable.
Indication :
- Mydriasis prior to retinoscopy
- Uveitis and keratitis
- To paralyze accommodation temporarily
Contraindications :
Patients with primary glaucoma or a predisposition to glaucoma; patients whose intraocular pressures are unknown; patients with narrow angle or shallow anterior chambers since they are susceptible to acute angle-closure glaucoma; hypersensitivity to belladonna alkaloids.
Dosing :
To produce cycloplegia and mydriasis for diagnostic purposes:
1 drop of 2% solution instilled in the eye(s) immediately prior to procedure; may be repeated at 10-minute intervals as needed.
Treatment of Uveal tract inflammation:
1 drop of 2% solution 2 or 3 times daily.
Adverse Effect :
Prolonged use leads to local irritation, increased intraocular pressure. Excessive use may produce atropine-like systemic effects (palpitations, dry mouth, constipation, thirst, tachycardia, visual disturbances, photophobia, flushed dry skin and temperature elevation). Higher doses may produce disorientation, headache, excitement, restlessness, delirium and hallucinations.
Interaction :
Pramlintide: Serious reaction with pramlintide. Monitor all other drugs being used at the same time.
Hepatic Dose :
No dosage adjustments are recommended.