[Types of topical treatment for peripheral neuropathic pain : Mechanism of action and indications].
The term "peripheral neuropathic pain syndromes" summarizes several chronic pain syndromes, which can occur focally or generalized in the peripheral nervous system in the course of an impairment of afferent neurons. Controlled clinical trials gave distinct indications for systemic treatments with antidepressants, anticonvulsants and opioid analgesics in several neuropathic pain syndromes. In addition to these systemic therapies, there are also two topical treatment options: topical application of lidocaine and capsaicin. An important cause of sensitization phenomena of afferent nociceptors is the upregulation of sodium channels and thermosensor channels. In the context of a partial nerve lesion that leaves behind partially preserved or regenerated afferent nerve fibres, just these channels could be used as target structures for topical medications. Topically applied drugs are absorbed systemically only in minute quantities, so systemic side effects are negligible. Pharmacological interactions with systematically acting substances are also virtually absent; thus, topically applied substances are especially appropriate for add-on therapy in addition to systemic pain medication.
Baron
R
R
Sektion Neurologische Schmerzforschung und -therapie, Klinik für Neurologie, Universitätsklinikum Schleswig-Holstein Campus Kiel, Haus 41, Arnold-Heller-Str. 3, 24105, Kiel, Deutschland. r.baron@neurologie.uni-kiel.de
Mahn
F
F
D000287:Administration, Topical; D000344:Afferent Pathways / Q000187:drug effects / Q000502:physiology; D000700:Analgesics / Q000008:administration & dosage / Q000627:therapeutic use*; D000779:Anesthetics, Local / Q000627:therapeutic use; D000928:Antidepressive Agents / Q000627:therapeutic use; D002211:Capsaicin / Q000627:therapeutic use; D006801:Humans; D008012:Lidocaine / Q000627:therapeutic use; D009412:Nerve Fibers / Q000187:drug effects / Q000502:physiology; D009416:Nerve Regeneration / Q000187:drug effects / Q000502:physiology; D009437:Neuralgia / Q000188:drug therapy* / Q000503:physiopathology; D010523:Peripheral Nervous System Diseases / Q000188:drug therapy; D018689:Sensory System Agents / Q000627:therapeutic use; D050916:TRPV Cation Channels / Q000187:drug effects / Q000502:physiology
D000700:Analgesics; D000779:Anesthetics, Local; D000928:Antidepressive Agents; D018689:Sensory System Agents; D050916:TRPV Cation Channels; D008012:Lidocaine; D002211:Capsaicin