I heard it is from the grain rye.
Answers (1)
Migergot contains caffeine and ergotamine.
The ergot found on rye is different to the pure ergotamine found in Migergot tablets.
You may find these links interesting:
http://www.ncbi.nlm.nih.gov/pubmed/14642357
http://www.drugs.com/mtm/migergot-oral-rectal.html
