Migraines are nasty! I get migraines also and I have used cannabis for my migraines with great success.
Typically you become aware that a migraine is coming because you will start to get neck pain with muscle spasms in your neck as a warning sign, so please, put high CBD topical salve on your neck to start to break the neck spasm. You also want to drink a large glass of water in case you're dehydrated and if it does make you vomit at least it will just be water and it will start to break the migraine. I drink a large mug of black coffee or black tea but careful if you are sensitive to caffeine. Then I will vaporize Jack Herer and my migraine is usually gone in about 15 to 20 minutes. I always reflect on what I have eaten or taken that has free glutamates since Glutamate's are neurologically toxic especially to migraine sufferers.
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Please be aware that once you do use Sativa During the day, you should not follow it with Indica that night because you will just bump the THC back up and you'll have a party in your head all night so please follow Sativa with CBDs. The CBD's will mind with the high THC You already have in your body and it will make a very powerful Indica and you likely will be asleep within an hour and wake up refreshed the next day. As you continue to take high CBD's you will notice that the severity and frequency of your migraines will greatly reduce and you will be able to get rid of the migraine much faster because you have more CBD's in your body.