The safety, tolerability, and efficacy of the
lidocaine patch 5% (
Lidoderm), a targeted peripheral
analgesic with an FDA-approved indication for the treatment of
postherpetic neuralgia, has been well established. Recent case reports and studies have suggested potential efficacy in other neuropathic and nonneuropathic
pain conditions. Several pharmacokinetic studies have demonstrated minimal systemic absorption with 12-, 18-, and 24-hour/day dosing. Mean maximum plasma concentrations have shown the
lidocaine patch to possess a minimal risk for systemic toxicities or
drug-drug interactions. The most common adverse events generally involve mild skin reactions. There have been no
drug-drug interactions noted in clinical trials. Recent evidence suggests that extended application does not result in A-beta-mediated sensory loss at the application site, which is particularly important in patients who already have a degree of sensory loss due to their underlying condition. The
lidocaine patch provides a treatment option that carries a relatively low systemic adverse event and
drug-drug interaction risk burden, even with continuous application of up to four patches per day.