Brand name for omeprazole. A wonderful drug if you suffer from chronic acid refulx. Usually, one dose inhibits the acid pumps in your stomach. I'm pretty sure it's the strongest thing they can give you. There are some problems though; one can't be on it for so long before you risk permanent side effects (I can't recall any longer though). There are also some short term side effects, such as headache, abdominal discomfort, nausea, and diharrea. None are too bad. And they're all easier to deal with than reflux. http://www.purplepill.com/ has more info on acid reflux disease, including active ingredients and side effects and all that good stuff (I'd list it here but I'd just be ripping it from the pdf file located at http://www.astrazenca-us.com/pi/Prilosec.pdf). Actually if you're interested in the medication, the pdf probably is more informative. Go there now. Run, frolic, play.
Prilosec more or less stops almost all production of stomach acids. I was on it for several months for severe acid reflux (it was leading to esophogedal bleeding, and "regular" antacids weren't doing the trick). It's side effects also include severe abdominal pain (although it's something like 1%). Most of the side effects are only present during the first week of usage (i.e. I got headaches at night for the first week), and don't all occur for all people (i.e. you might get none, Sally might get them all, and Billy might get 1).