An estimated 15 million Americans suffer from heartburn every day, but not everyone will need "the purple pill" (Nexium) or another Proton-Pump Inhibitor (PPI) drug to treat it. PPIs are a class of very effective and generally safe medicines used to treat heartburn, gastroesophageal reflux disease (GERD), and gastric ulcers.

PPIs have been heavily promoted, which has led to overuse in people with garden-variety heartburn. Nexium, one of the most widely-prescribed PPIs is also the most expensive at $240 per month (the cash price you would pay if your insurance did not cover it). Not surprisingly, Nexium was also a top-selling drug in 2008 at a whooping $4.8 billion.

Before you turn to a PPI, consider this: If you have occasional heartburn and have not been diagnosed with gastroesophageal reflux disease (GERD), your first and best bet is to try an inexpensive over-the-counter antacid like Maalox, Mylanta, Rolaids, Tums, or generic or drugs like Pepcid AC or Zantac 150, or generic (known as H2 blockers).

But if you suffer from heartburn twice a week or more for weeks or months on end, you should see a doctor because you may have GERD often known as acid reflux. GERD is serious and can inflame or erode the lining of the esophagus. PPIs are effective at treating GERD.

So here's the good news: The latest Consumer Reports Best Buy Drugs analysis of drugs to treat heartburn, GERD and gastric ulcers finds that among the six available PPI drugs, no drug works better than another and all are relatively safe. Two drugs—omeprazole (Prilosec, Prilosec OTC) and lansoprazole (Prevacid, Prevacid 24HR)—are available as a prescription and a nonprescription drug. Two others—omeprazole and pantoprazole (Protonix)—are available as a brand-name drug and a generic, which contains the same active ingredient but costs significantly less.

(See links above to download the full PDF report or a 2-page summary report.)

Taking the evidence for effectiveness, safety, cost, and other factors into account, if you need a PPI, we have chosen the following as Consumer Reports Best Buy Drugs:

• Prilosec OTC
• Generic omeprazole OTC

Another option might be the nonprescription version of Prevacid, called Prevacid 24HR. The Food and Drug Administration recently approved it for sale without a prescription and it is expected on store shelves in mid-November 2009. We expect it will cost about the same as Prilosec OTC.

Safety notes: Several studies have linked PPIs to a higher risk of pneumonia and infection with a bacterium called Clostridium difficile, and other studies have found that long-term use of PPIs may be associated with an increased risk of hip fractures. Talk with your doctor about those risks, especially if you must take a PPI over a long period of time. People ages 65 and over and those with chronic medical conditions should be vaccinated against pneumonia and get a flu shot every year and we emphasize this recommendation for people in those categories who are also taking a PPI.

In addition, anyone taking clopidogrel (Plavix), a blood thinner used to prevent clots after heart attacks and stent placement, should be especially cautious with PPIs. Some studies indicate that PPIs may reduce clopidogrel's effectiveness, which could increase the risk of another heart attack. Our medical advisers recommend that people taking clopidogrel should not take PPIs unless other remedies have not been adequate.