Products
Lidocaine patches have been approved in many countries since 1999 and 1995 (Neurodol, Emla + Prilocaine).
Structure and properties
Lidocaine (C14H22N2O, Mr = 234.3 g/mol) exists as a white crystalline powder that is practically insoluble in water. It is an amide-type local anesthetic.
Effects
Lidocaine (ATC D04AB01) has local anesthetic, membrane stabilizing, and analgesic properties. It blocks sodium channels in peripheral nerve fibers, inhibiting conduction. It is effective in the epidermal and dermal layers of the skin, and only a small percentage of the dose is absorbed into the bloodstream.
Indications
- For relief of pain associated with postherpetic neuralgia (Neurodol).
- Topical anesthesia of intact skin associated with minor procedures or surgical treatment of minor local lesions (Emla).
Dosage
According to the professional information. The patch should be used only on intact skin.
Contraindications
Lidocaine is contraindicated in hypersensitivity, acute shingles, and atopic dermatitis. For complete precautions, see the drug label.
Interactions
Lidocaine should be combined only with caution with antiarrhythmic agents and CYP3A4 inhibitors. However, because of low plasma levels, drug-drug interactions are considered rare.
Adverse effects
Possible adverse effects include local skin reactions such as swelling, redness, itching, and a burning sensation. Systemic adverse effects are rare but may occur with overdose.
