Subcutaneous injection of botulinum toxin a is beneficial in postherpetic neuralgia.
OBJECTIVE
To assess the benefits of subcutaneous injection of botulinum toxin A (BTX-A) for the treatment of postherpetic neuralgia (PHN).


METHODS
We investigated the therapeutic benefits of BTX-A in subjects with PHN in a randomized, double-blind, placebo-controlled study. Sixty subjects with PHN were randomly and evenly distributed into BTX-A, lidocaine, and placebo groups.


METHODS
After randomization, one of the following solutions was injected subcutaneously in the affected dermatome: 5u/mL BTX-A, 0.5% lidocaine, or 0.9% saline (placebo). Visual analog scale (VAS) pain and sleeping time (hours) were evaluated at the time of pretreatment, day 1, day 7, and 3 months posttreatment. Opioid usage was calculated at day 7 and 3 months posttreatment.


RESULTS
Compared with pretreatment, VAS pain scores decreased at day 7 and 3 months posttreatment in all three groups (P<0.01). However, the VAS pain scores of the BTX-A group decreased more significantly compared with lidocaine and placebo groups at day 7 and 3 months posttreatment (P<0.01). Sleep time (hours) had improved at day 7 and at 3 months compared with pretreatment in all three groups, but the BTX-A group improved more significantly compared with lidocaine and placebo groups (P<0.01). The percent of subjects using opioids posttreatment in the BTX-A group was the lowest (21.1%) compared with the lidocaine (52.6%) and placebo (66.7%) groups (P<0.01).


CONCLUSIONS
Subcutaneous administration of BTX-A significantly decreased pain in PHN and reduced opioid use compared with lidocaine and placebo at day 7 and 3 months post-treatment. It also increased subjects' sleep times.
Department of Pain Management of Shenzhen Nanshan Hospital, Guangdong Medical School, Nanshan Shenzhen, China. xlz99@tom.com
Lizu
L
Xiao
Sean
S
Mackey
Hui
H
Hui
Donglin
D
Xong
Qian
Q
Zhang
Deren
D
Zhang
D000701:Analgesics, Opioid / Q000627:therapeutic use; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000627:therapeutic use; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage* / Q000627:therapeutic use*; D004311:Double-Blind Method; D006801:Humans; D007279:Injections, Subcutaneous; D008012:Lidocaine / Q000008:administration & dosage / Q000627:therapeutic use; D051474:Neuralgia, Postherpetic / Q000188:drug therapy*; D009465:Neuromuscular Agents / Q000008:administration & dosage* / Q000627:therapeutic use*; D010147:Pain Measurement; D010919:Placebos / Q000627:therapeutic use; D011446:Prospective Studies; D011788:Quality of Life; D016896:Treatment Outcome
D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D009465:Neuromuscular Agents; D010919:Placebos; D008012:Lidocaine; D019274:Botulinum Toxins, Type A