Afflicted with chronic migraines? You might be suffering from a cannabinoid deficiency. Cannabis shows promise as a viable treatment for migraines. A new study indicates that medical marijuana significantly drops the frequency of migraines. Interestingly enough, cannabis was the standard treatment for migraines from 1874 to 1942. This “new” treatment is now being studied for efficacy.

Researchers at the Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of Colorado Anschutz Medical Campus studied 121 patients between 2010 and 2014. Out of the 121 patients, 103 saw a decrease in migraines. On average, migraines dropped from 10.4 to 4.6 migraines per month, a figure that is considered clinically significant.

The study was published January 9th in the journal Pharmacotherapy.

Professor Laura Borgelt, PharmD, FCCP, BCPS, is senior author of the study. “There was a substantial improvement for patients in their ability to function and feel better,” wrote Borgelt. “Like any drug, marijuana has potential benefits and potential risks. It’s important for people to be aware that using medical marijuana can also have adverse effects.”

Patients were gathered at Gedde Whole Health, a Colorado-based practice that focuses on cannabis treatments. Researchers found that inhaled cannabis was better suited for instantly treating acute migraines. They also found that edibles take longer to take effect, but help prevent headaches.

Positive effects were the most commonly reported outcome from the trial. 85 percent of participants reported decreased frequency of migraines, and 14 patients reported that the migraines had ceased altogether. “There were some patients who reported more than 15 migraines per month before using cannabis. After using cannabis, they were reduced to one to two migraines per month,” researcher Danielle Rhyne said.

Cannabinoids play an important role by affecting critical neurotransmitters like serotonin and dopamine. “We believe serotonin plays a role in migraine headaches, but we are still working to discover the exact role of cannabinoids in this condition,” Borgelt said.

An earlier report in 2007 in the European Journal of Critical Pharmacology suggested that patients with chronic migraines have low levels of the endogenous cannabinoids anandamide and 2-arachidonylglycerol (2-AG). “These data support the potential involvement of a dysfunctioning of the endocannabinoid and serotonergic systems in the pathology of chronic migraine and medication-overuse headaches,” they wrote.

Borgelt added that only a randomized, placebo-controlled clinical trial would definitively enable medical marijuana to be proven effective. Federal laws, however, have gotten in the way. “If patients are considering medical marijuana they should speak to their health care provider and then follow up so we can track the impact of their overall treatment,” Borgelt said. “Open communication is necessary because we need to know how all of these treatments work together.”

It is currently unknown which strains are more effective for migraines. “Further research should be performed to determine if there is a preferred delivery method, dose, and strain of medical marijuana for migraine headache therapy as well as potential long-term effects of medical marijuana,” researchers concluded.