Source: Medicines and Medical Devices Safety Authority (NZ) Revision Year: 2018 Publisher: Pharmaco (NZ) Ltd, 4 Fisher Crescent, Mount Wellington, Auckland 1060, New Zealand. PO Box 4079, Auckland 1140, New Zealand. Free Phone: 0800 804 079.
Pharmacotherapeutic group: Sensory organ; ophthalmologicals; local anaesthetic
ATC Code: SO1HA04
Proxymetacaine hydrochloride is a potent topical anaesthetic of the ester type.
The main site of anaesthetic action is the nerve cell membrane where proxymetacaine interferes with the large transient increase in the membrane permeability to sodium ions that is normally produced by a slight depolarisation of the membrane. As the anaesthetic action progressively develops in a nerve, the threshold for electrical stimulation gradually increases and the safety factor for conduction decreases; when this action is sufficiently well developed, block of conduction is produced.
The exact mechanism whereby proxymetacaine and other local anaesthetics influence the permeability of the cell membrane is unknown; however, several studies indicate that local anaesthetics may limit sodium ion permeability through the lipid layer of the nerve cell membrane. This limitation prevents the fundamental change necessary for the generation of the action potential.
Proxymetacaine hydrochloride is a rapid acting local anaesthetic suitable for ophthalmic use. With a single drop, the onset of anaesthesia usually begins within 30 seconds and persists for 15 minutes or longer.
Proxymetacaine hydrochloride is a potent topical anaesthetic of the ester type.
After topical administration, proxymetacaine hydrochloride is absorbed into the system and generally decomposes quickly in the plasma; however, high doses can cause undesirable systemic effects.
The carcinogenic potential of proxymetacaine hydrochloride has not been investigated in long-term animal studies.
No study has been conducted to determine the potential proxymetacaine hydrochloride.
© All content on this website, including data entry, data processing, decision support tools, "RxReasoner" logo and graphics, is the intellectual property of RxReasoner and is protected by copyright laws. Unauthorized reproduction or distribution of any part of this content without explicit written permission from RxReasoner is strictly prohibited. Any third-party content used on this site is acknowledged and utilized under fair use principles.
