ES is a smooth muscle relaxant used for th epurpose of relaxing the bile duct that is part of the smooth muscle in the body. Smooth muscle is only ONE kind of body muscle. I feel that some people are too low in mag and the body uses it first to correct the body of it's depletion until that depletion is corrected. I never could take enough of it to allow the bile duct to dilate enough to let the stones pass. Tried twice the dose that comes with the Clark flush, was in bed for 18 hours post the flush, got extremely lethargic/weak and it took me a whole day to recover, too. If the liver dam isn't opened up enough and the stones don't pass, it will affect the blood pressure. Just one person's experience.
If the colon is in bad shape from the encrusted fecal matter, the body will pull out a lot of fluid causing dehydration along with the diarrhea. You can't dehydrate a sick body and expect to get well. The Clark flush is NOT for everybody, IMO.