Effect of high-dose lidocaine treatment on superoxide dismutase and malon dialdehyde levels in seven diabetic patients

Background and Objectives: We report on the use of intravenous (IV) high-do se lidocaine to relieve diabetic neuropathic pain, and the technique's effe cts on clinical measures of lipid peroxidation. Methods: Under continuous electrocardiogram monitoring, IV lidocaine (5 mg kg(-1) in 100 mt saline) was administered over 30 minutes to 7 non-insulin- dependent diabetic patients suffering from neuropathic pain who reported in creased pain within the preceding 6 months. This treatment was performed on ce a week for 1 month. Blood samples were collected from the contralateral limb to determine plasma superoxide dismutase (SOD) and malondialdehyde (MD A) levels on admission and following the final lidocaine administration. Results: Plasma MDA concentrations significantly decreased after the final TV lidocaine treatment (P < .05, paired t-test), whereas SOD levels did not show a statistically significant difference compared with baseline levels. Conclusions: High-dose lidocaine treatment lessens MDA levels, a marker of free-radical-mediated cell damage. This suggests that one of lidocaine's me chanism of action may be its effect on oxygen free radicals, which in turn impacts lipid peroxidation.