Lidocaine infusion may provide short-term pain relief for refractory neuropathic pain, according to a study published in Regional Anesthesia & Pain Medicine.
This double-blind, placebo-controlled study was conducted to assess whether repeated intravenous administration of low-dose lidocaine (3 mg/kg) could provide safe and effective prolonged pain relief for postherpetic neuralgia or complex regional pain syndrome type II.
After a 7-day screening period, 42 patients age 18 to 80 years with a diagnosis of either postherpetic neuralgia or complex regional pain syndrome type II were randomly assigned into 2 groups.
Participants in the control group received an intravenous infusion of saline, and those in the lidocaine infusion therapy group received a low-dose infusion of lidocaine once a week for 4 consecutive weeks. There were no significant differences in demographics or baseline numeric rating scale pain scores between the 2 groups.
There were no serious adverse effects of lidocaine infusion therapy, and numeric rating scale pain scores recorded after each infusion demonstrated its efficacy. Reduction in pain was reported by those in the lidocaine infusion group from baseline to after the final infusion (P =.011) compared with the control group. However, significant pain relief was not observed at 4-week follow-up (P =.028), even in the group that had previously received 4 consecutive lidocaine infusions. This suggests a transient effect for lidocaine.
“Repeated infusions may be needed to evaluate the dependable efficacy of [lidocaine infusion therapy] for pain relief,” the researchers wrote. “Alternatively, oral lidocaine may be needed to maintain the effects of [lidocaine infusion therapy].”
“This infusion protocol proved to be safe and effective for managing patients with [neuropathic pain] in an outpatient clinic, with no adverse events requiring hospitalization,” they concluded.
Kim Y-C, Castañeda AM, Lee C-s, Jin H-S, Park KS, Moon JY. Efficacy and safety of lidocaine infusion treatment for neuropathic pain: A randomized, double-blind, and placebo-controlled study [published online January 29, 2018]. Reg Anesth Pain Med. doi:10.1097/AAP.0000000000000741