From what I understand about Colon Cleanses is this is what takes place. This Salwater Cleanse is just a safer way to do it.
It is not necessarily diarrhea, but just the salt water making its way through, I remember "The Master Cleanse" mentioning it(saltwater) has the same specific gravity as your blood therefore it is not going to be taken through your kidneys or your blood. So, then there's only one other option for elimination, your bowels.
I just started the "lemonade" today, but last night I drank Laxative Tea & woke up at 7am wide awake. Within 10 minutes I had bad gas cramps, I attempted to go but nothing happened, this went on for 15 minutes. I decided to drink my saltwater and as I got through 1/2 a quart I needed to go #2 a couple times. I then laid down and within another 20 minutes, the saltwater was ready to come out. Just for getting an idea about how much time this can take, I woke up at 7am for about 45 minutes I actually had to worry about #2, then I took a shower. Be careful of sneezes because you will have an accident, so make sure all of the saltwater gets out. So about 8:15am, I was pretty much in the clear, I did my hair for 20 minutes then laid back down. Then got back up and left for work around 9am.
I am not afraid to do this on work days, just make sure you have an hour to spare. Believe me, I am no early riser, but the "lemonade diet" should give you more energy to make it through, if not the Laxative Tea you take the night before:)