Caffeine is a natural stimulant most commonly found in tea, coffee and cacao plants.

It works by stimulating the brain and central nervous system, helping you to stay alert and preventing the onset of tiredness.

Acute treatment of headaches with caffeine is sometimes effective, but should be limited to not more than two days per week.

 Reference : https://americanmigrainefoundation.org/resource-library/caffeine-and-migraine/ , July 2th, 2019