I'm so glad you found relief! As you read up on magnesium you'll find that an issue with the supplements is they all can cause diarrhea at "high" doses. So folks who need more magnesium can consider taking a lower dose 200 mg supp every couple hours to bowel tollerance and try to get to 1000mg/day. Taking allot at one time causes bowel reactions.
This is a very old fashioned solution: Milk of Magnesia and Magnesium Citrate!