I go through periods of fairly severe acid reflux and have tried many different brands of anti acids. The one that I have found that really works well for me is Pecid Complete.
Pepcid Complete contains Famotidine, Calcium Carbonate, and Magnesium Hydroxide and is for the relieve of heartburn, acid indigestion and sour stomach. I use the tablets.
The one thing I really like about this brand is that the tablets are not chalky and are easy to chew and swallow without giving me the feeling that there is a lump in my throat. Indeed, Pepcid also has a tablet called Easy Chews which are even easier to chew and swallow. Both the regular and the Easy Chews, however, contain the same ingredients and work the same way for the same stomach upsets. Another thing I like is that Pecid does not give me the feeling of a bloated stomach like some anti acids do.
Of course, Pecid Complete works very well. It is fast and really is complete meaning that one is all you need. I have never had to take more than one to get fast and lasting relieve. In fact, you should not take more than 2 tablets in a 24 hour period. As with any drug, OTC or otherwise, please talk to your doctor before using especially if you are taking other medications.
Pepcid costs a little more than store brands but it is definitely worth it. Check out their web site at http://www.pepcid.com/