proxymetacaine hydrochloride: clinical use

Prescribing considerations

• Not intended for regular or prolonged use because repeated topical ocular anaesthesia can damage the corneal epithelium.
• Use additional caution in patients with known allergies, cardiac disease, hyperthyroidism or an inflamed eye.
• Inflamed conjunctiva can increase systemic absorption; punctal occlusion can reduce nasolacrimal drainage, particularly in children.
• Protect the anaesthetised eye from rubbing, chemicals and foreign bodies.

Contraindications and cautions

• Known hypersensitivity to any component of the preparation
• Avoid in premature infants because ester local-anaesthetic metabolism is immature

Monitoring

• Observe for immediate corneal hypersensitivity, epithelial damage or inflammation.
• Confirm that transient visual disturbance has resolved before driving or hazardous activity.
• If repeated procedural application is necessary, assess corneal integrity and avoid unintended prolonged exposure.

Clinical pharmacology

Proxymetacaine reversibly blocks initiation and conduction of nerve impulses by reducing neuronal sodium permeability. Systemically absorbed medicine is hydrolysed by plasma esterases and also undergoes hepatic metabolism.

Formulation and product differences

• The selected product is a clear, colourless to pale-yellow, preservative-free ophthalmic solution in sterile single-use containers.
• Discard each container after opening and reject solution that is darker than pale yellow.
• Refrigerated storage is required unless the pharmacy has applied an appropriate shortened room-temperature expiry label; do not freeze.

Eye drops

Route: Ophthalmic

Strengths: 0.5% w/v