Does anyone know a good over-the-counter remedy for heartburn? I got it so bad with my first pregnancy, and I'm only 6 weeks and already have it again!

Last time my OBs prescribed me Losec, which was amazing, but we're going away on Saturday and I won't have time to see a doctor before then, and I'm not sure if Losec is okay in first trimester (I only started taking it in third trimester last time).

So anything you've found that works that you can just buy from a chemist? I've tried Rennies, and aside from the fact that I HATE them, they only work for about five minutes and then it's back. I can't believe how miserable it can make me!