I forgot to add this to my previous post but I also found that it helped when I would take them at different times of the day instead of together. If you take a multi-vitamin with iron, be sure and take that at a different time than you take your calcium also. That will help a bunch with absorbtion. It took my vitamins wrong for about a year before discovering this site and read the vitamin details. It really helps to try Heather's suggestions. I wish you lots of luck and relief soon!!