Neuropathic Pain
Conditions
Brief summary
Pain as a result of nerve injury (neuropathic pain) is a particularly severe form of chronic pain. Common examples of neuropathic pain are pain due to diabetes and shingles. There is good evidence that an intravenous infusion of lidocaine (local anesthetic) is useful for the management of neuropathic pain in the short term - up to six hours.
Detailed description
This study will examine the role of intravenous lidocaine in the relief of neuropathic pain over four weeks following infusion compared to an active placebo infusion of diphenhydramine(Benadryl) in normal saline. If we can show that intravenous lidocaine provides sustained benefit for up to one month, this will be a major advance in the management of individuals suffering from neuropathic pain.
Interventions
Lidocaine 5 mg/kg in 250 ml of normal saline infused over 45 minutes.
Diphenhydramine 50 mg in 250 ml of normal saline infused over 45 minutes.
Sponsors
Study design
Eligibility
Inclusion criteria
* Chronic neuropathic pain due to diabetes mellitus or herpes zoster and a score of 4/10 or greater on the DN4 questionnaire. * Moderate to severe pain as defined by screening average pain intensity of 5 or greater on a 0-10 numerical rating scale. * Neuropathic pain duration of at least 6 months.
Exclusion criteria
* Presence of clinically significant cardiac disease. * Poorly controlled seizure disorder. * Significant psychiatric disorder. * History of allergy to lidocaine or any other amide local anesthetic * History of allergy to diphenhydramine. * Prior treatment with a local anesthetic infusion. * Neuropathic pain due to cancer or complex regional pain syndrome * Language barrier or cognitive impairment that would preclude understanding of the study and filling out of questionnaires * Lack of a driver to transport the patient to and from the pain clinic.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Changes from Baseline Pain scores on the Visual Analog Scale at 4 weeks | every 24 hours for four weeks post-infusion |
Secondary
| Measure | Time frame |
|---|---|
| Modified Brief Pain Inventory | obtained baseline, 24, 72 hours and then weeks 1,2,3 and 4 |
| Leeds Sleep Evaluation Questionnaire | obtained baseline, 24, 72 hours and then weeks 1,2,3 and 4 |
| Hospital Anxiety and Depression Scale | obtained baseline, 24 and 72 hours and then weeks 1,2,3, and 4 |
| Side Effects | obtained baseline, 24, 72 hours and then weeks 1,2,3 and 4 |
| Quality of Life Health Outcome Instrument | obtained baseline, 24, 72 hours and then weeks 1,2,3 and 4 |
| Patient Global Satisfaction with Treatment and Impression of Change | obtained baseline, 24, 72 hours and then weeks 1,2,3 and 4 |
Countries
Canada