The 5% Lidocaine-Medicated Plaster: Its Inclusion in International Treatment Guidelines for Treating Localized Neuropathic Pain, and Clinical Evidence Supporting its Use.
When peripheral neuropathic pain affects a specific, clearly demarcated area of the body, it may be described as localized neuropathic pain (LNP). Examples include postherpetic neuralgia and painful diabetic neuropathy, as well as post-surgical and post-traumatic pain. These conditions may respond to topical treatment, i.e., pharmaceutical agents acting locally on the peripheral nervous system, and the topical route offers advantages over systemic administration. Notably, only a small fraction of the dose reaches the systemic circulation, thereby reducing the risk of systemic adverse effects, drug-drug interactions and overdose. From the patient's perspective, the analgesic agent is easily applied to the most painful area(s). The 5% lidocaine-medicated plaster has been used for several years to treat LNP and is registered in approximately 50 countries. Many clinical guidelines recommend this treatment modality as a first-line option for treating LNP, particularly in frail and/or elderly patients and those receiving multiple medications, because the benefit-to-risk ratios are far better than those of systemic analgesics. However, some guidelines make only a weak recommendation for its use. This paper considers the positioning of the 5% lidocaine-medicated plaster in international treatment guidelines and how they may be influenced by the specific criteria used in developing them, such as the methodology employed by randomized, placebo-controlled trials. It then examines the body of evidence supporting use of the plaster in some prevalent LNP conditions. Common themes that emerge from clinical studies are: (1) the excellent tolerability and safety of the plaster, which can increase patients' adherence to treatment, (2) continued efficacy over long-term treatment, and (3) significant reduction in the size of the painful area. On this basis, it is felt that the 5% lidocaine-medicated plaster should be more strongly recommended for treating LNP, either as one component of a multimodal approach or as monotherapy.
Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität zu Kiel, Kiel, Germany. r.baron@neurologie.uni-kiel.de.
Ralf
R
Baron
Pain Therapy Service, Azienda Ospedaliera Universitaria Parma Hospital, Parma, Italy.
Massimo
M
Allegri
Rehabilitation Department, Hospital del Trabajador de Asociación Chilena de Seguridad, Santiago, Chile.
Gerardo
G
Correa-Illanes
Multidisciplinary Pain Centre, Antwerp University Hospital, Edegum, Belgium.
Guy
G
Hans
University Department of Anaesthesia, Pain Research Office, Gartnavel General Hospital, Glasgow, Scotland, UK.
Michael
M
Serpell
Centre for Pain Evaluation and Treatment, University Neurological Hospital, Lyons, France.
Gerard
G
Mick
Anaesthesiology Department, Hospital Universitario de Bellvitge, El Hospitalet de Llobregat, 08907, Barcelona, Spain.
Victor
V
Mayoral
5% lidocaine-medicated plaster; Allodynia; Ease of use; Efficacy; Guidelines; Localized neuropathic pain; Long-term safety; Postherpetic neuralgia; Quality of life; Reviews