Revista de la Sociedad Española del Dolor
versión impresa ISSN 1134-8046
Introduction: Neuropathic pain results from nervous system injury or dysfunction. Medical treatment is the first line therapy, including antidepressants, anticonvulsants and other drugs. The analgesic efficacy of opioids in the treatment of neuropathic pain is controversial. Methadone is a Ì-opioid receptor agonist, which also acts by blocking norepinephrine and serotonin reuptake into the dorsal horn, and is an N-methyl-D aspartate (NMDA) receptor antagonist. Objective: To evaluate the clinical characteristics of patients with non-oncological neuropathic pain treated with methadone. Material and methods: We performed a retrospective, cross-sectional study. Medical records were reviewed and patients with neuropathic pain taking methadone were interviewed between January 1 and July 31, 2006 to evaluate reduction of pain intensity, dosing, and side effects. Results: We included 31 patients with neuropathic pain who received methadone treatment. The patients were taking between 2.5 mg and 60 mg per day of methadone (mode 10 mg per day). Pain intensity on the Visual Analog Scale was 8.7 ± 1.2, and 4.3 ± 1.8, before and after treatment with methadone, respectively, with a mean decrease of 49%. The most frequent adverse effect was constipation (65%). Conclusions: Methadone is a useful drug in the treatment of neuropathic pain when other drugs have failed.
Palabras clave : Neuropathic pain; Methadone; Adverse effects.