Cannabinoid Use in a Tertiary Headache Clinic: A Cross-Sectional Survey

Objective: This study seeks to determine the prevalence and nature of cannabis use in patients with headache in a tertiary headache clinic and to explore patients' empiric experience in using cannabinoids therapeutically. Background: Many patients with headache report cannabinoid use as an effective abortive and/or preventive therapy. Mounting evidence implicates cannabinoids in pain mechanisms pertaining to migraine and other headache types. Methods: A cross-sectional study surveyed 200 patients presenting with any headache disorder to a tertiary headache clinic in Calgary, Alberta. Descriptive analyses were applied to capture information about headache diagnoses and the frequency, doses and methods of cannabinoid delivery employed, as well as patients' perceptions of therapeutic benefit and selected negative side effects. Results: Active cannabinoid users comprised 34.0% of respondents. Approximately 40% of respondents using cannabinoids engaged in very frequent use (>= 300 days/year). Of cannabinoid modalities, liquid concentrates were most popular (39.2%), followed by smoked cannabis (33.3%). Patients endorsed cannabinoid use for both prevention and acute therapy of headaches, often concurrently. Sixty percent of respondents felt cannabinoids reduced headache severity, while 29.2% perceived efficacy in aborting headaches. Nearly 5% of respondents volunteered that they had encountered a serious problem such as an argument, fight, accident, or work issue as a result of their cannabis use. Approximately 35.4% of users had attempted to reduce their use. Conclusion: This survey shows that over one-third of patients with headache disorders in a tertiary headache clinic use cannabis as a treatment for their headaches. Of these, about 25% and 60% perceive improvements in headache frequency and severity, respectively. The results of this survey will aid neurologists and headache specialists in understanding the landscape of cannabinoid use in a more severely affected population and inform future-controlled studies of cannabinoids in headache patients.