Liquid minerals....there much better absorbed...although sometimes taste pretty bad...and they will help with any cleansing process. There are many different brands in health food stores...just make sure that they also contain trace minerals.
The problem with the Epsom Salts is not that you're absorbing them...it is because they induce diarrhea or loose stools that causes you to lose electrolytes. While you are getting some magnesium from the ES, if you take it at levels to flush you out...you're losing more than you're gaining...especially potassium.