Vasotrop

Approved Indications:

• Mydriasis (pupil dilation) for diagnostic procedures: Used prior to fundus examination, retinoscopy, or other ophthalmic diagnostic tests requiring dilation.
• Pre-operative and intra-operative mydriasis in ocular surgeries.
• Uveitis and iritis: To prevent or break posterior synechiae and reduce the risk of iris adhesions.
• Anterior uveitis-induced photophobia and pain: To alleviate discomfort by paralyzing the ciliary muscle and dilating the pupil.

Clinically Accepted Off-Label Uses:

• Cycloplegia for refraction assessment in children or adults with suspected latent hyperopia or accommodative spasm.
• Assessment of Horner's Syndrome (phenylephrine sensitivity testing using low concentration).

Adults (including elderly):

• For diagnostic mydriasis: Instill 1 drop in the eye(s), may repeat after 5–10 minutes if needed.
• Typical combination formulation: Tropicamide 0.8% + Phenylephrine HCl 5%.
• Max effect: within 20–40 minutes.
• Duration: Dilation may last 4–6 hours; up to 24 hours in sensitive individuals.

Children:

• Dosing must be adjusted carefully and supervised by pediatric ophthalmologists.
• Usually 1 drop, with lower concentrations recommended (e.g., phenylephrine 2.5% instead of 5%).
• May repeat after 10 minutes if necessary.

Special Populations:

• Renal or hepatic impairment: No specific dose adjustment, but caution advised.
• Cardiovascular disease or hyperthyroidism: Use lower phenylephrine concentration (2.5%) and monitor closely.

Route of Administration:

• Topical ophthalmic (eye drops).

Precautions for Administration:

• Apply pressure to the nasolacrimal duct for 1–2 minutes post-instillation to reduce systemic absorption.
• Do not touch dropper tip to any surface.

Tropicamide is a short-acting anticholinergic agent that blocks muscarinic receptors in the iris sphincter muscle and ciliary body, leading to mydriasis (pupil dilation) and cycloplegia (loss of accommodation). Phenylephrine Hydrochloride is a direct-acting sympathomimetic alpha-1 agonist that causes contraction of the dilator pupillae muscle, enhancing pupil dilation without affecting accommodation. Together, they synergistically induce maximal mydriasis, with Tropicamide primarily inhibiting parasympathetic tone and Phenylephrine stimulating sympathetic tone.

• Absorption: Rapidly absorbed through the corneal and conjunctival tissues; some systemic absorption via nasolacrimal duct and mucosa.
• Onset of action: 10–30 minutes post-instillation.
• Peak effect: 20–60 minutes.
• Duration: Tropicamide—4–6 hours; Phenylephrine—3–7 hours; up to 24 hours in sensitive individuals.
• Metabolism: Tropicamide undergoes hepatic metabolism; phenylephrine is metabolized in the liver and intestines by monoamine oxidase.
• Elimination: Renal excretion of metabolites.
• Bioavailability: Primarily topical effect; systemic bioavailability low but clinically significant in sensitive populations (e.g., infants, elderly).

• Pregnancy: Limited data; generally considered Category C (based on individual components). Should only be used during pregnancy if the potential benefit justifies potential risk.
• Lactation: Tropicamide and phenylephrine may be excreted in breast milk. Use with caution; avoid frequent or high-dose use in nursing mothers. Temporary interruption of breastfeeding may be considered.
• Caution advised due to potential systemic anticholinergic or sympathomimetic effects in infants.

• Primary Class: Mydriatic and Cycloplegic Agent (Ophthalmic)
• Subclass:
• Tropicamide: Anticholinergic (parasympatholytic)
• Phenylephrine: Sympathomimetic (alpha-1 adrenergic agonist)

• Known hypersensitivity to tropicamide, phenylephrine, or any excipients
• Narrow-angle or angle-closure glaucoma
• Severe cardiovascular disorders (e.g., unstable angina, recent MI)
• Uncontrolled hypertension
• Hyperthyroidism or thyrotoxicosis
• Infants with known susceptibility to systemic anticholinergics

• Elderly patients: Increased risk of acute angle-closure glaucoma.
• Infants and young children: More susceptible to systemic toxicity (e.g., CNS or cardiac effects).
• Cardiovascular risk: Systemic absorption of phenylephrine may increase BP or cause arrhythmia.
• Psychiatric/CNS effects: Tropicamide may cause confusion, hallucinations, or behavioral disturbances.
• Monitoring: Intraocular pressure monitoring advised in glaucoma-susceptible patients.
• Ophthalmic use only: Not for systemic or intraocular injection.
• Avoid driving or operating machinery until visual function normalizes.

Common (mild to moderate):

• Eye: Transient stinging, blurred vision, photophobia, dryness
• Systemic (rare): Flushing, dry mouth, headache

Less Common:

• Increased intraocular pressure
• Allergic conjunctivitis or eyelid edema

Serious (rare but critical):

• Cardiovascular: Tachycardia, hypertension, arrhythmia
• CNS: Restlessness, hallucinations (especially in children)
• Acute angle-closure glaucoma (in predisposed individuals)
• Seizures (rare)

• Monoamine Oxidase Inhibitors (MAOIs): Potentiate hypertensive effect of phenylephrine.
• Tricyclic Antidepressants: May enhance systemic pressor effects.
• Beta-blockers: May increase systemic hypertensive risk when combined with phenylephrine.
• Other anticholinergics: May enhance systemic side effects (e.g., dry mouth, confusion).
• Enzyme systems: Phenylephrine is metabolized by MAO; concurrent inhibitors affect duration and intensity of action.

• Phenylephrine 2.5% preferred over 5% in infants, elderly, and patients with cardiovascular risks (recent consensus updates).
• Updated caution on systemic absorption risks in neonates and elderly—emphasizing nasolacrimal occlusion techniques post-instillation.
• EMA and FDA reminders: Use lowest effective dose to minimize systemic effects, especially in pediatric patients.

• Temperature: Store at 15°C to 25°C (59°F to 77°F); avoid extremes.
• Humidity/Light: Protect from light and moisture.
• Handling: Keep cap tightly closed. Do not use if solution becomes discolored or cloudy.
• Refrigeration: Not required for most commercial brands.
• Discard period: Use within 30 days after opening unless otherwise labeled.