Cannabis Can Cause “Rebound” Migraine Headaches, Study Finds
Migraine sufferers who use cannabis for pain relief may be at higher odds of developing a “rebound” headache, also known as a medication overuse headache (MOH), according to new research from scientists at Stanford University.
The Stanford scientists reviewed medical records from over 360 patients who had chronic migraine – defined as having 15 or more headache days per month – covering a period of at least one year, concluding that “cannabis use significantly contributes to the prevalence of MOH” in chronic migraine.
The preliminary study will be presented at the American Academy of Neurology’s 73rd Annual Meeting, which is due to take place virtually on April 17-22, 2021.
Cannabis use as a predictor for medication overuse headaches
While the evidence base supporting cannabis’ use as an acute treatment for migraine continues to grow, to date there has been little research looking at the mid- to long-term health effects of cannabis use on people with chronic migraine.
“Many people with chronic migraine are already self-medicating with cannabis, and there is some evidence that cannabis can help treat other types of chronic pain,” Niushen Zhang, a clinical assistant professor at the Stanford University School of Medicine, said in a statement.
“However, we found that people who were using cannabis [for chronic migraine] had significantly increased odds of also having medication overuse headache, or rebound headache, compared to people who were not using cannabis.”
Looking at the medical records of 368 patients living with diagnosed chronic migraine for over a year – 150 of whom reported using cannabis – the researchers recorded the prevalence of medication overuse headache (MOH) in each group, along with other important information on migraine frequency and any concurrent medications.
They found that people using cannabis were six times more likely to have MOH than those who did not use cannabis. In total, 212 of the 368-person study sample reported experiencing MOH.
People who were using opioids were also more likely to have current cannabis use, which would support the findings of at least one recent addiction study which concluded that cannabis does not curtail illicit opioid use as first thought.
This link between cannabis and opioids and migraine also presents an interesting area for investigation, as previous research has shown that opioids and cannabis can both influence the periaqueductal gray region of the brain, which has itself been linked to chronic migraine pathophysiology.
What is a medication overuse headache?
Medication overuse headaches (MOHs) are triggered by the long-term use of painkillers or triptan medications in patients with underlying migraine or headache disorders.
A person with chronic migraine might take painkillers to deal with a migraine attack and then choose to take another dose as the earlier medication wears off and the pain begins to return. If this is repeated frequently, the painkiller use can quickly become a cycle where the migraine sufferer ends up regularly overusing the drugs, to the point where the medication overuse begins to cause its own headaches. By that point, even when the painkiller use is stopped, many migraine sufferers will experience chronic headaches as a result of medication withdrawal.
In recent years cannabis has started to be floated as a possible alternative method of pain relief for migraine, given the anecdotal success of many other chronic pain sufferers in treating their conditions with legal cannabis. Early studies also appear promising; one published in the Journal of Pain found inhaled cannabis to reduce the severity of headaches and migraines by around fifty percent.
While this new work has certain limitations due to its retrospective nature, the researchers hope that the study will prompt the development of more detailed longitudinal studies that can better explore the cause and effect of cannabis use on medication overuse headache in chronic migraine patients.