I was recently diagnosed with GERD and began taking Prilosec after dietary changes failed to lessen painful heartburn symptoms that accompanied every meal. While I was on Prilosec, the heartburn disappeared. However, I often had the uncomfortable sensation that my stomach was bloated and yet very empty at the same time. Because of insurance coverage changes, I switched to Prevacid, and the discomfort has disappeared. My doctor says that Prilosec and Prevacid are interchangeable. Do you know of any differences between the two drugs?

N.

People with gastroesophageal reflux disease (GERD) often see a doctor after trying over-the-counter medications such as antacids. The doctor may recommend other more effective anti-acid medications, such as ranitidine (Zantac). However, a small percentage of patients, usually ones with more severe reflux changes seen on endoscopy in the esophagus, will not respond fully to these medications. These patients usually receive a more potent class of drugs called proton-pump inhibitors (PPIs).

PPIs include omeprazole (Prilosec) and lansoprazole (Prevacid), as well as the newly released rabeprazole (Aciphex). Laboratory studies done on PPIs have found only minor differences in their activity, and clinical studies done with patients show no differences among the drugs with respect to symptom relief or healing of esophagitis.

I am not surprised that your symptoms of GERD disappeared with both Prilosec and Prevacid. However, while the scientific data indicate all PPIs have similar side effects. I have often been told by various patients that one drug or the other seems to suit them better. The bloating you felt while on Prilosec could have been a medication side effect. It could also have a coincidental symptom of GERD, unrelated to the drug.

If you are doing well with Prevacid, there is no reason to change your medication. If bloating or other side effects happen to return, check with your doctor to make sure no other problem exists.