I did it about
4 years ago and no prep except no food after midnight the night before. Like Sniper said, it's a little larger than a big vitamin, but it's smooth plastic and really easy to swallow. I was worried about
that and made them bring me a huge glass of water. Thankfully, it slid right down, no problem. Mine did get stuck and they removed it when I had my resection about
a month later, so I'd take the advice saying do the dissolving pill first, if you have that option.