DYNEXAN OINTMENT

Indications

• Local anesthesia for minor surgical procedures
• Dental procedures requiring local anesthesia
• Topical anesthesia for mucous membranes

Dosage

Children: Refer to BNF for Children for appropriate dosing guidelines in pediatric populations.

Adults: Refer to the BNF for recommended dosages, which may vary based on the specific procedure and formulation used.

Mechanism of action

Amethocaine produces local anesthesia by blocking sodium ion channels involved in the initiation and conduction of neuronal impulses, preventing the propagation of action potentials in nerve fibers.

Pharmacodynamics

The local anesthetic effects of amethocaine occur through the reversible inhibition of sodium channels in neuronal membranes. By preventing sodium influx during depolarization, amethocaine effectively stabilizes the neuronal membrane, leading to a decrease in nerve excitability and conduction. This results in a loss of sensation in the targeted area.

Pharmacokinetics

Amethocaine is well-absorbed at the site of administration. It has a relatively slow systemic absorption rate compared to other local anesthetics due to its higher lipid solubility. The onset of action is rapid, typically within minutes, and the duration of effect can last from 1 to 3 hours, depending on the concentration used. Metabolism occurs primarily in the plasma by hydrolysis through esterases, and it is excreted in the urine as metabolites.

Adverse effects

• Allergic reactions
• Local irritation
• Nausea
• Dizziness
• Hypotension

Precautions

• Use with caution in patients with a history of hypersensitivity to local anesthetics
• Monitor for signs of systemic toxicity, especially in large doses or when used in sensitive areas

Pregnancy

Amethocaine should only be used if the potential benefit justifies the potential risk to the fetus. Consult with a healthcare professional.

Breast-feeding

Use with caution, as it is not known whether amethocaine is excreted in breast milk.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Topical solution
• Ointment
• Gel

Mechanism of action

Tetracaine is an ester-type anesthetic and produces local anesthesia by blocking the sodium ion channels involved in the initiation and conduction of neuronal impulses.