Depending on the severity of the prolapse, you definately need to take the snake to the vet.
Soaking the snake in shallow water should help keep the tissues healthy, and also help in cleaning the exposed tissue off.
The sugarwater trick is a myth. I've never seen it work, and I've seen prolapses in a few different reptile species and sugar water was tried in all of them. Chemically speaking, all that table sugar is is a bunch of hydrogen molecules, some carbon, some oxygen. It is not going to do much in helping the rectum go back where it belongs.
If it is a small prolapse and you can only see a little bit of pink tissue, a shallow soak and being kept overnight on damp papertowels should be enough to let the swelling go down on its own. If it is more than that or the tissue has dried and will not go back to normal on its own, take it to a vet ASAP as it requires very delicate maneuvering (and possible surgery) to get it back into place.
~jenny
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"Polysyllabism in no way insures that what you're saying is actually worth being heard." - Blake (an e-friend of mine)
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