Why would you want to do one? Definetly check with your doctor first. One of my doctors once told me to not do a colon cleanse ever! He said not only do they clean you out, they also clean out the good stuff and can cause problems. He didn't see a need to ever do one.
I do not think so as the gas will simply come back when it feels like it. To me it seems like one more way of making yourself more miserable, without a good reason. You can probably guess I am very anti "colon cleansing" unless medically required.
I have gotten colon cleanses routinely about 2-3 times per year for years. I think they are very beneficial to my overall health. I feel wonderful after it is done. My practictioner is very well educated and uses safe, closed methods that include measures to restore the good instestinal flora.
I do plan to have another this year, but not for a couple of months out. My doctor had to do a lot of work to remove adhesions during my surgery and I don't want to do anything to encourage their reformation. So I am going to wait to be sure I am completely healed.
I know that colon cleanses aren't the most popular topic but I hope this helps in some way.