Cannabinoids in Multiple Sclerosis: A Neurophysiological Analysis

Objectives: To investigate the action of cannabinoids on spasticity and pain in secondary progressive multiple sclerosis, by means of neurophysiological indexes.

Material and methods: We assessed 15 patients with progressive MS (11 females) using clinical scales for spasticity and pain, as well as neurophysiological variables (H/M ratio, cutaneous silent period or CSP). Testing occurred before (T0) and during (T1) a standard treatment with an oral spray containing delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Neurophysiological measures at T0 were compared with those of 14 healthy controls of similar age and sex (HC). We then compared the patient results at the 2 time points (T1 vs T0).

Results: At T0, neurophysiological variables did not differ significantly between patients and controls. At T1, spasticity and pain scores improved, as detected by the Modified Ashworth Scale or MAS (p=0.001), 9-Hole Peg Test or 9HPT (p=0.018), numeric rating scale for spasticity or NRS (p=0.001), and visual analogue scale for pain or VAS (p=0.005). At the same time, the CSP was significantly prolonged (p=0.001).

Conclusions: The THC-CBD spray improved spasticity and pain in secondary progressive MS patients. The spray prolonged CSP duration, which appears a promising tool for assessing and monitoring the analgesic effects of THC-CBD in MS.