Matropin

• Ophthalmic use
• Induction of mydriasis (pupil dilation) for diagnostic procedures such as fundus examination.
• Cycloplegia: paralysis of the ciliary muscle to relieve pain in uveitis or iritis and aid accurate refraction testing.
• Treatment of anterior uveitis/iritis
• Reduces ocular pain and photophobia by relaxing the ciliary muscle and preventing synechiae formation.
• Adjunctive therapy
• Sometimes used postoperatively to maintain pupil dilation during eye surgery.

Administered topically as ophthalmic drops.

• Adults
• Standard concentration: 0.5–2% solution.
• Typical dose: 1–2 drops in the affected eye every 4–6 hours.
• Cycloplegia for uveitis: 1 drop every 1–2 hours initially, then taper as symptoms improve.
• Pediatrics
• Lower concentrations (0.25–1%) may be used; dosing individualized based on age and response.
• Elderly
• Usually same as adult dosing; monitor for systemic anticholinergic effects due to increased sensitivity.
• Special populations
• Renal/hepatic impairment: No specific adjustments; use caution with systemic absorption.
• Remove contact lenses before administration; wait at least 15 minutes before reinsertion.

Homatropine is a muscarinic acetylcholine receptor antagonist. By competitively blocking muscarinic receptors in the iris sphincter and ciliary muscle, it induces pupil dilation (mydriasis) and paralysis of accommodation (cycloplegia). In cases of uveitis or iritis, relaxation of the ciliary muscle reduces pain from ciliary spasm, and dilation of the pupil prevents posterior synechiae formation, preserving normal iris-lens configuration and preventing adhesions.

• Absorption: Minimal systemic absorption via conjunctival vessels; local ocular effects occur within 30–60 minutes.
• Distribution: Confined mainly to the anterior chamber of the eye; negligible systemic distribution at standard topical doses.
• Metabolism: Metabolized in the liver if absorbed systemically.
• Excretion: Primarily renal via urine following systemic absorption; most activity is local.
• Onset & duration: Pupil dilation typically begins 20–30 minutes after instillation; cycloplegia can last 6–12 hours depending on concentration.

• Pregnancy: Category C. Use only if clearly needed; systemic absorption is minimal but caution is advised.
• Lactation: Minimal systemic absorption; not expected to affect breastfed infants. Monitor for anticholinergic effects if significant exposure occurs.

• Primary therapeutic class: Anticholinergic / mydriatic agent.
• Subclass: Muscarinic receptor antagonist.

• Known hypersensitivity to homatropine or other anticholinergic agents.
• Narrow-angle glaucoma or patients at risk of acute angle-closure glaucoma.
• Severe cardiovascular disease or tachyarrhythmia when systemic absorption is possible.
• Obstructive uropathy or gastrointestinal obstruction (caution with systemic absorption).

• Glaucoma: Can precipitate acute angle-closure glaucoma in predisposed individuals; monitor intraocular pressure.
• Systemic anticholinergic effects: Rare but may include dry mouth, tachycardia, urinary retention, or confusion, especially in the elderly.
• Photosensitivity: Pupillary dilation increases light sensitivity; recommend sunglasses after instillation.
• Contact lenses: Remove prior to administration; wait at least 15 minutes before reinsertion.
• Pediatric caution: Increased sensitivity to systemic anticholinergic effects; monitor closely.

• Ocular
• Blurred vision, photophobia, transient stinging or burning.
• Conjunctival hyperemia or irritation.
• Systemic (rare)
• Dry mouth, headache, dizziness, flushing, tachycardia.
• Urinary retention or constipation in susceptible individuals.
• Severe/rare
• Acute angle-closure glaucoma in predisposed patients.
• Confusion or agitation in elderly patients after systemic absorption.

• Other anticholinergics: Additive effects may increase risk of systemic anticholinergic side effects.
• Glaucoma medications: May antagonize miotic agents used to lower intraocular pressure.
• No CYP450 interactions: Minimal systemic metabolism; primarily local ocular activity.

• Current ophthalmology guidelines recommend homatropine primarily for uveitis management and diagnostic cycloplegia.
• Preference over atropine for shorter duration cycloplegia to reduce prolonged blurred vision.
• Careful use advised in elderly and glaucoma patients with appropriate intraocular pressure monitoring.
• Emerging recommendations suggest low-dose formulations for pediatric patients to minimize systemic effects.

• Temperature: Store 20°C–25°C (room temperature); protect from excessive heat.
• Light & humidity: Keep in tight, light-resistant container; avoid moisture.
• Handling precautions: Do not touch dropper tip to any surface or eye; discard after expiration.
• Reconstitution: Not applicable; supplied as ready-to-use ophthalmic solution.