Intravenous lidocaine in central pain: a double-blind, placebo-controlled, psychophysical study.
OBJECTIVE
To investigate the effects of systemic administration of lidocaine on different components of neuropathic central pains by quantitative sensory testing.


METHODS
The efficacy of systemic lidocaine (5 mg/kg IV over 30 minutes) was evaluated in a double-blind, placebo-controlled, and cross-over fashion, on both spontaneous ongoing pain and evoked pains (allodynia and hyperalgesia) in 16 patients with chronic poststroke (n = 6) or spinal cord injury (n = 10) related pain.


RESULTS
Lidocaine was significantly superior to the placebo (saline) in reducing the intensity of spontaneous ongoing pain for up to 45 minutes after the injection: 10 of 16 patients (62.5%) receiving lidocaine showed a significant reduction in spontaneous pain, whereas only six patients showed this after the placebo. Lidocaine also significantly reduced the intensity of brush-induced allodynia and mechanical hyperalgesia, but was no better than the placebo against thermal allodynia and hyperalgesia. In general, the side effects were moderate and consisted mainly of lightheadedness (44%).


CONCLUSIONS
Systemic lidocaine can induce a significant and selective reduction of several components of pain caused by CNS injuries. The observed preferential antihyperalgesic and antiallodynic effects of this drug suggest a selective central action on the mechanisms underlying these evoked pains.
Attal
N
N
Centre d'Evaluation et de Traitement de la douleur, Hôpital Ambroise Paré, Boulogne, Paris, France.
Gaudé
V
V
Brasseur
L
L
Dupuy
M
M
Guirimand
F
F
Parker
F
F
Bouhassira
D
D
D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008012:Lidocaine / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology; D013119:Spinal Cord Injuries / Q000150:complications*; D020521:Stroke / Q000150:complications*; D013997:Time Factors
D008012:Lidocaine