Date of Award


Degree Type

Selective Evidence-Based Medicine Review

Degree Name

Master of Science in Health Sciences - Physician Assistant


Physician Assistant Studies

Department Chair

John Cavenagh, MBA, PhD, PA-C


OBJECTIVE: The objective of this selective EBM review is to determine whether or not “Is Tetrahydrocannabinol (THC)/Cannabidiol (CBD) oromucosal spray an effective adjuvant therapy for Multiple Sclerosis (MS) patients who suffer from central neuropathic pain (CNP)?”

STUDY DESIGN: Systematic review of three randomized controlled trials published between 2005-2013, all English language.

DATA SOURCES: Three randomized controlled studies were obtained using PubMed and MedLine.

OUTCOMES MEASURED: The outcome of each study was the subject’s incidence and severity of central neuropathic pain compared to their baseline at the beginning of the study. Outcomes were measured using an 11-point pain scale at various intervals. The average scores of these participants were used to compare the control group versus the intervention group.

RESULTS: Three randomized controlled trials and uncontrolled, extension trial were used in this review. Langford et al demonstrated a mean difference between the THC/CBD group and placebo-controlled group to be (odds ratio 1.31 [95% CI, 1.01-2.57 points]; P=0.046) after 10 weeks. Rog et al found that there was a statistically significant mean reduction of pain intensity (Mean change -2.7; 95% CI: -3.4 – 2.0 (p=0.005)) in the THC/CBD intervention group. Hoggart et al showed a significant mean reduction in pain scores (-0.96 points; 95% CI: -1.59, -0.32, (p=0.004)) when compared to control group. All of the results were observed in patients who were already on a stable regimen of analgesic medications to treat neuropathic pain related to MS.

CONCLUSIONS: All three studies demonstrated statistically significant reduction in mean central neuropathic pain with THC-CBD oromucosal spray as compared to baseline, as well as compared to a placebo-control group. The addition of THC/CBD oromucosal spray should be considered in MS patients who suffer from central neuropathic pain and do not receive pain relief from standard therapy.