I can see a couple of possibilities. One is that many bowel cleanses use harsh stimulant laxatives such as senna, cascara sagrada, rhubarb root or cape aloe (Aloe ferox) concentrates. So you may want to see if any of these are in the product..
Psyllium is well known for causing gas and bloating, and it is very hard on the intestines. Especially if there are inflammatory conditions such as diverticulitis, Crohn's or ulcerative colitis.
And ginger is great for protein digestive enzymes, but it is also an antacid. Neutralizing the stomach acid can contribute to acid reflux.