Lidoderm Patches

The Lidocaine 5% patch also known as Lidoderm is another treatment option. It directly targets the pain while avoiding negative systemic effects. The patch slowly releases the medication transdermally over a twelve hour period. Lidoderm produces an analgesic effect by blocking sodium channels which decreases the sensitivity of pain receptors and CNS excitability.12 It has also been shown to prevent the production of macrophage-induced nitric oxide which produces inflammation during cartilage degeneration and rheumatic disease. It also inhibits T-cell production thereby inhibiting them from producing inflammation of the synovium and destroying cartilage. Because it is administered transdermally it decreases adverse events. However if it is applied to broken skin adverse events may occur.13

Current recommended dosage of the lidoderm patch is as many as three patches applied once daily for a 12 hour period. It is recommended the patient then practices a twelve hour “off period”.12
In a study of 30 patient s with knee OA the lidoderm patch was used as the sole treatment for the OA pain. Researchers found significant improvement in pain levels and quality of life in a two week period. For various pain assessments anywhere between thirty-six and fifty-seven percent of patients reported a fifty percent reduction of pain.12

Another study of using the lidocaine patch for knee OA found similar results in a 2-week open label non-randomized study. 100 patients were treated with the lidoderm patch; some as the sole source of treatment and some as an addition to other conservative treatments. Researchers used the Neuropathic Pain Scale (NPS) and found significant improvement in all four measures for both groups of patients. There were no adverse events in patients in the mono-therapy group; however five patients in the add-on therapy group exhibited AEs.13