If you did not stay sufficiently hydrated during the flush you will feel lousy afterward, or at least that has been my experience. That is why I don't eat after 2:00 pm, but I ignore the don't drink after 2:00pm rule. I even chase down the Epsom Salt drinks with a glass of water (immediately- and no, it doesn't seem to dilute the impact of the Epsom Salts ), and then a full glass of water an hour afterward. If I get up in the night to go to the bathroom (usually do 2-3 times), I stop by the kitchen on the way back to bed and drink a glass of water. As long as I keep pushing the water I feel fine the next day.