Hi - mostly a lurker, but just had to post this...
I'm 29 weeks pregnant with my first and have been fortune enough to have a relatively niggle free pregnancy so far (albeit high risk due to pre-existing conditions).
The exception has been heartburn... and it's awful! I had never suffered from it before and can't believe some poor people have to live with this on a daily basis.
Anyway, I tried everything in the past 5 weeks (Gaviscon Advance, Rennie, bland meals, milk, sitting/sleeping as upright as possible, love hearts, ice cream, lemonade, almonds, you name it) and nothing worked; if anything it was getting worse and I was feeling ill even after a glass of water.
Spoke to my consultant yesterday who told me that if I was truly desperate he would write a prescription for ranitidine, but asked me if I would be happy to try something milder first. He gave me a bottle of something called Maalox and after 2 swigs I've been heartburn free for hours! Hours, I tell you! As a bonus, it's nowhere near as revolting as Gaviscon liquid 
I think he said you can actually get OTC, which I'm fine with me... I would pay anything to get rid of that torture!
Apologies for the long, slightly hysterical post but I'm truly over the moon 