Hashish Use Linked to Elevated Prevalence of MOH Amongst Continual Migraineurs

The results of a retrospective study show that cannabis use significantly contributes to the prevalence of headache associated with overuse of medication (MOH) in patients with chronic migraine (CM). Individuals also showed a bidirectional cannabis-opioid association, with use increasing use of the other.

Based on the results, researchers suggest that advising patients with CM and MOH to reduce cannabis use may be beneficial in order to effectively treat MOH. The abstract will be presented at the 73rd annual meeting of the American Academy of Neurology, which is practically April 17-22, 2021.

MOH results from the regular overuse of acute headache medication such as triptans, ergot, barbiturates or opiates in patents with pre-existing primary headache disorders. Cannabis affects the endocannabinoid system in the brain, which plays a role in pain processing, the researchers explained. Although some evidence supports the use of cannabis for the treatment of chronic pain, individual evidence suggests that the use of cannabis may lead to MOH.

To determine whether cannabis use predicts MOH in patients with CM, the researchers used the Stanford Repository Cohort Discovery Tool to evaluate data from 368 adult patients with CM (150 with cannabis, 218 without cannabis) who had been on it for at least 1 year Suffering from illness.

Data collected between 2015 and 2019 included variables such as age, gender, frequency of migraines, current CM duration, current cannabis use duration, excessive use of other drugs for acute migraines, and information about MOH. The researchers then used logistic regression to identify variables that predict MOH while controlling the remaining predictors. In addition, agglomerative hierarchical clustering (AHC) was performed to determine natural clusters using all predictor variables.

Of the patients with CM included, 212 experienced MOH and 156 did not. Analyzes showed:

  • Current cannabis use predicted statistically significant cases with MOH (odds ratio) [OR] 5.99; P <0.0001)
  • Significant associations were found between current cannabis use, opioid use, and MOH
  • AHC found that cluster I patients were younger, had fewer migraines, had higher MOH exposure, and consumed more cannabis and opioids than cluster II

Overall, people who used cannabis were six times more likely to have MOH than people who didn’t, while patients who used opioids were more likely to be currently using cannabis. Both cannabis and opioids can affect the periaqueductal gray area of ​​the brain, which has been suggested as a possible trigger of migraine attacks.

“Many people with CM are already self-treating themselves with cannabis, and there is evidence that cannabis may help treat other types of chronic pain,” said study author Niushen Zhang, MD, said the likelihood of having MOH or headaches is also significantly increased compared to people who did not use cannabis. “

Because the analysis was retrospective, future longitudinal studies are needed to better understand the cause and effect of cannabis use and MOH in patients with CM.


Zhang N and Woldeamanuel Y. Headache from drug overuse in chronic migraine patients who use cannabis: a case study. Abstract Presented at American Academy of Neurology’s 73rd Annual Meeting; 17.-22. April 2021; Virtual. Accessed March 1, 2021.