Colon cleansing review

Before my father passed away 5 years ago, his doctor said, that out father needed to have a colon cleansing because his small intestine is hard to circulate the food he eat. I went online and search for the colon cleansing review if it is really good before we spend money. Believe me or not after having colon cleansing. My father is able to eat anything without any problem going to the bathroom constantly. We all scared because my father is getting very skinny and he also had stage 4 lung cancer that make him even more very sick.