My experience with Epsom Salts . For me, with liver flushing, it never kicked in until the following morning. However in the context of a bowel clease, after being empty and doing a SWF, it seems to kick in rather quickly - a couple hours. So, I guess it depends on how much and what you ate during the day. Some just seem more sensitive to it. You could probably cut back and see what happens.

As far as sleep - it's over rated. What happens with the flush is going to happen in the first hour, anyway. Just try to lay still for at least 30 minutes. So, if you gotta go, then go.

There is no danger in walking, getting up, or not sleeping.
The only problem of not sleeping is that you may feel tired the next day. Other then that, you should pay your visit to the restroom whenever you feel like. Always listen to your body. It is smarter then you or enyone else.

White Shark