Short summary

The study is a randomized, double-blinded, controlled trial on cannabis based medication in peripheral neuropathic pain.The study population will include 150 patients with chronic peripheral neuropathic pain caused by polyneuropathy, postherpetic neuralgia, and nerve damage due to trauma or surgery. The patients will be randomly allocated into four groups. Three groups will receive cannabis based medication (CBD, THC or combination THC and CBD) and one group will receive placebo. The treatment will last for 8 weeks. The patients will be allowed to continue current treatment of neuropathic pain with the exception of strong opioids, or they can be drug free (no treatment for neuropathic pain)

Rationale

Treatment of peripheral neuropathic pain is unsatisfactory, with less than half of the patients achieving good pain relief using the usual drugs. Predictors for the effects of different drugs are available to a limited extent. Peripheral neuropathic pain is one of the types of pain that cannabis is claimed to work on, but the evidence is ambiguous. Recent systematic reviews have come up with conflicting conclusions with regard to evidence of the use of cannabinoids for chronic neuropathic pain. 

The purpose of this project is to clarify whether the major active components of cannabis, Tetra-Hydro-Cannabinol (THC) and Cannabidiol (CBD) can provide clinically significant pain relief in peripheral neuropathic pain and if treatment can be used without clinically significant mental side effects.

Description of the cohort

Men and women (> 18 years) with chronic peripheral neuropathic pain (> 6 months) caused by polyneuropathy, postherpetic neuralgia or nerve damage due to trauma or surgery. 

Data and biological material

Blood samples

ECG

Questionnaires (incl. dairies)

Autonomic nerve testing (Vagus test)

Collaborating researchers and departments

Dansk Smerteforskningscenter og Smerteklinik ved Neurologisk afdeling, Aarhus Universitetshospital 

• Professor Nanna B. Finnerup, MD
• Professor Flemming W. Bach, MD

Multidisciplinær Smerteklinik og Endokrinologisk afdeling, Rigshospitalet

• Consultant Thomas P. Enggaard, MD
• Consultant Merete Petersen, MD

Komplikationsforskning, Steno Diabetes Center Copenhagen, Gentofte

• Post. doc Christian Stevns Hansen, MD