Its not bad at all. the prep is no fun, but tollerable. You'll be amazed at how much you get out of your colon. I'm convinced the cleansing is a huge treatment alone. I do suggest getting a hemoroid(sp?) cream of some kind. I use Nupercanal. It is expensive, but amazing. It kept my mom from having hem. surgery, and it really helps more than anything else I've ever tried for irritation. ( i also use it for everyday itches, etc.)
When you go in, they will start an IV. They will take you into a procedure room. they usually/may give you 02, and put a monitor on your finger and blood pressure cuff(maybe). You'll see lots of monitors and tv looking things, and possible see the scopes they use. They will then ask you to lay on your side. they push the meds, you feel a little smilely and things get a little spinny/blurry and they next thing you know, your waking up. I usually always have to relieve the gas a lot, but it goes away in a few hours. My first scope, I slept for hrs. afterward. now I am wide awake shortly after.
I hope this helps, and I hope your test goes well.
PS: drink lots of fluid right up untill your not suppose to have anymore. That helps with cramps, and fatigue. Lots and lots of water and gatoraid. I suggest some gatoraid b/c it give you electrolites, etc. Get some jello or something you enjoy. they should have given you a list of foods you can eat. eat NOTHING RED. They sometimes looks like blood, so its a no no.