Has he considered trying accupuncture? Also yoga is good, and try to make sure he drinks a lot of water, and don't let him skip meals.
Make sure he gets his vitamins too!
Also, make sure he gets enough sleep.
A book I have found useful is this one:
Title: Migraine for Dummies
Authors: Dianne Stafford and Jennifer Shoquist MD
I hope you find it as helpful as I have!
You can read about the book here too: http://www.dummies.com/WileyCDA/DummiesTitle/productCd-0764554859.html
I got my copy from the local library (I live in the UK).
Let me know how you get on