I had this early in my treatment also. I didn't have it as bad as you do but laxatives didn't work for me either.
The solution is simple really. So simple you may not believe it. It is castor oil!!
If you read Kalcker's parasite protocol, castor oil is recommended daily. To get things going, take a full dose of 2-4 tablespoons, then you could take just 1 teaspoon or so daily to keep things moving.