CBD is one of more than five hundred cannabinoids present in the cannabis plant.1 While there is no known cure for migraines we know that cannabidiol oil relieves pain and reduces inflammation. 2 
Until recently, largely due to legal and political reasons, there has been little research using CBD as a migraine treatment. Nonetheless there is considerable mention of cannabis in antiquity as it relates to headaches.
“Assyrian manuscripts from the second millennium BCE recommended cannabis to ‘bind the temples,’ and Ayurvedic preparations in the third and fourth centuries BCE were indicated for ‘diseases of the head’ such as migraines. The prescription of cannabis was ... recommended in ancient Greece ... as a treatment for 'pain of the ears,” as well as in the Islamic world. "Prominent physicians of the Middle Ages ... also recommended the use of cannabis for headache.“ 3
Now that cannabis research is no longer on the legal back burner we find numerous ongoing efforts to cultivate cannabis varietals that target migraine relief. Cannabis strains vary widely in their "composition of cannabinoids, terpenes, flavonoids, and other compounds. These components produce wide variations in benefits, side effects, and strain characteristics” that “will enable targeting individual symptoms and/or diseases, including migraine “4
It can be hoped that not too long from now we will have effective treatments for migraine sufferers.
1. https://www.nccih.nih.gov/health/cannabis-marijuana-and-cannabinoids-what-you-need-to-know
2. https://www.medicalnewstoday.com/articles/321653#why-it-might-help
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5436334/
4. https://headachejournal.onlinelibrary.wiley.com/doi/full/10.1111/head.13345