Magnesium oxide question, Colosan

I have done a series of liver cleanses using first the colonsan for a week. Then doing one liver cleanse a month using the epsom salts for 10 months. My question is can this actually cause problems? I felt better after the liver cleanses but I also got much more constipated with hard dry stools that I never had before the cleanses. I tried to take the colasan again to improve this situation and i had severe muscle cramping all over my body. Is is possible to get a magnesium calcium ratio out of wack using these products? Depleteing me of something?