Another explanation of water with sapo/kambo

Thought I just wrote about this but then today someone asked if it was necessary to drink a gallon of water prior to sapo/kambo use. This is what I wrote:
If you do the medicine Matses style, Sapo style, there is no drinking of water beforehand. But the Matses were hunter/gatherers when I met them, still eating tree barks for carbohydrates because they did not have fields. They would put pineapple tops down to make them grow on hunting paths and such, but they were not yet agrarian. What they needed sapo for was to clean them out, steady their hand with a bow and arrow, allow them to walk several days with little sleep, little food, and little water. Now the Brazilian groups that we subsequently learned about who used sapo, did it Kambo style: The Katukina and Yaminawa were more agrarian and fishermen and less depending on hunting. So it might be--and this is only my hypothesis--that they suffered more stomach ailments because of their diet, and so needed the Kambo to clean their stomachs out. Their style emphasised drinking water--one or two liters, never a gallon, which could kill a person who weighed under 100 lbs--to help produce vomiting, which would clean out the stomach of rotten material. So your question is "is it necessary to drink lots of water prior to sapo/kambo use" and the answer is: IF you want to concentrate the medicine on cleansing the stomach, drinking a liter of water will ensure vomiting, and probably vomiting bile. If you want a full body detox and reset, do not drink water and do not worry about vomiting, because the Matses never thought of that as necessary for the medicine do do the work.