Botulinum toxin a improved burning pain and allodynia in two patients with spinal cord pathology.

OBJECTIVE: To report the effect of botulinum toxin A in two patients with burning pain and allodynia of spinal cord origin.

DESIGN, SETTING, PATIENTS: Two patients with spinal cord lesions at the cervical level (tumor and stroke) experienced exquisite skin sensitivity and spontaneous burning pain in dermatomes corresponding to the cord lesions. Botulinum toxin A (Botox) was injected subcutaneously at multiple points (16 to 20 sites, 5 units/site) in the area of burning pain and allodynia.

RESULTS: Both patients reported significant improvement in spontaneous burning pain and allodynia in visual analogue scale and clinical measures. The analgesic effect of botulinum toxin A lasted at least 3 months and was sustained over follow-up periods of 2 and 3 years with repeated administration at 4-month intervals.

CONCLUSION: Subcutaneous application of botulinum toxin A relieved central burning pain and allodynia in two patients with spinal cord pathology.