Plain old baking soda works best, be sure to follow the instructions carefully. You can actually overdose on this due to the high sodium content. Yes, it tastes icky but works super fast and is cheap.

My father was a doctor and my mother was an RN. They both swore by Titralac. I know it's available; I recently saw it at Walmart. It tastes ok, and it works well. I haven't been able to find out whether it has corn starch. It does have no sugar, but does contain saccharin.

Also, make sure you don't take those proton pump inhibitors for too long unless your doctor says it's alright. Recently there was a warning posted for those medications:

Prolonged treatment with prescription PPIs may lead to low serum magnesium levels, which can result in serious adverse events including muscle spasm (tetany), irregular heartbeat (arrhythmias), and convulsions (seizures).

http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm245275.htm

I would say if you need to ask, you should check in with your doctor. Having said that, here's an overview of the three "levels" of mediciation

If you are looking for short term relief take something like tums or rolaids which neutralizes acid in your stomach on contact. If you are looking for longer term acid control try Zantac or Pepcid. Those are H2 blockers. H2 tells your body to make acid for digestive purposes, by blocking the H2 you make less acid. It won't block acid caused by stress and such, but it will cut down on your overall supply of acid.

If that doesn't work, you could take some of the PPIs for a short duration (Prilosec and the like) but PPIs are actually permenantly destroying the pumps in your stomach, something that strong isn't for long term use (in my opinion). It takes a couple of weeks for the PPI to work, then you should keep up with it for a couple of weeks to make sure your stomach and esophagus have time to heal. Then switch to zantac. PPIs only work in the presence of acid, so you can't take the H2 blockers at the same tome as the PPIs... But really, again, I emphasize, go visit your doctor about your heartburn, it could be an ulcer.

In my experience (suffered from heartburn for about 15 years), a little milk or a piece of bread is the best remedy for heartburn. I think the milk neutralizes some of the acid - and it's cold, an added bonus, and the bread seems to absorb some of the excess acid so that there's no reflux. I've tried Zantac, which worked okay, and I've heard mixed things about Prilosec, but my solution is considerably cheaper, and works really well for me. Good luck.

I have always had luck with aluminum hydroxide/magnesium hydroxide products such as Maalox, Mylanta, & Milk of Magnesia. Tastes bad but works great.

@missallergic123: Any idea what set off the heartburn? I realized that sugar and sugary foods did it for me along with certain tomato sauce products that have added sugar to them. I've cut sugar completely out of my diet (along with quite a few highly processed foods) and have had only 2 incidents of heartburn in the last decade. Two. I used to get heartburn at least 3 or 4 times a week. The trade off has been worth it. I know, it's a real PITA but if you can avoid the triggers, might be something for you to consider. It got me totally off the meds.

@thefenst: cool thing I learned when I had severe nausea during my pregnancies, Mylanta tastes the same going down as it does coming back up!

I have acid reflux and my doctor has given me Aciphex. It works great, best thing I have ever used.
Might be a little much for you, but a great product.

@missallergic123: In addition, with the exception of maalox, I'd stay away from all the medications recommended so far. The apple was an excellent suggestion, and the reason red apples work better than green is the higher concentration of pectin, which is also in the white, pithy stuff that's on citrus fruit peels. Either of those will be helpful. Too bad about the dairy, but I'm not surprised, given your username.

I didn't see where anyone mentioned pecid complete. This works for me, almost immediately. Unfortunately, it has been really hard to find in the stores for the last 12 months or so. Something about stocks of them turning moldy while warehoused. Baking soda has also worked for me. Prilo OTC works, but the effects seem to wear off two days after taking a two week course. I take the prilo when I'm on an extended trip or during the holiday season.

A table spoon of apple cider vinegar with a cup of water seems to do it for me.

@nathenastle: water makes heartburn worse.