Ametop Gel 4% (Tetracaine)

Mechanism of action

Tetracaine is believed to act by blocking nerve conduction mainly by inhibiting sodium ion flux across the axon membrane. Tetracaine achieves this by acting upon specific receptors that control gating mechanisms responsible for conductance changes in specialised proteinaceous sodium channels.

Blocking sodium ion flux prevents the setting up of an action potential in the nerve axon, thus preventing pain receptors signalling to the central nervous system.

Contraindications:

• Do not apply Ametop gel to broken skin, mucous membranes or to the eyes or ears.
• Hypersensitivity to the active substance, to local anaesthetics of the ester type, or to any of the excipients.

Special warnings and precautions for use:

• Only apply to intact, normal skin.
• Not to be taken internally.
• Ametop gel, like other local anaesthetics may be ototoxic and should not be instilled into the middle ear or used for procedures which might involve penetration into the middle ear.
• Repeated exposure to Ametop gel may increase the risk of sensitisation reactions to tetracaine.
• Although the systemic availability of tetracaine by percutaneous absorption of Ametop gel is low, caution should be exercised in patients with epilepsy.
• Ametop contains Sodium methyl-p-hydroxybenzoate (E219) and Sodium propyl-p-hydroxybenzoate (E217) which may cause allergic reactions (possibly delayed).