What Causes Severe Constipation And Gastritis While On Benazepril?

My doctor has me taking Benazipril Guanfacine and spironolactone htzc together. I feel blah with gas pains loose stool and now a feeling of constapation. He said to take all three but I have read that they should not be taken together. I want to stop all medication until tomorrow and then take only the benazipril and Guanfacine.is this the right thing to do? I am also trying to flush it out with water.