You feel the burn, so you assume there's too much acid. Your doctor agrees and prescribes a suppressor. But what if the real problem is the opposite? In many people, reflux is caused by too little acid, not too much. The Heidelberg test measures your acid output directly, so you actually know which one it is.
Most people who show up with heartburn get the same response: too much acid, take this. PPIs are among the most prescribed drugs on the planet. Every prescription is built on the same assumption: the stomach is overproducing acid and suppressing it will fix the problem.
For some people, that's exactly right. For others, it's exactly wrong.
When stomach acid is low, food stays in the stomach too long. The stomach stretches. Pressure builds. The valve at the top opens. Stomach contents wash upward. You feel burning. The sensation is identical whether acid is high or low. You can't tell the difference from the outside. Only a direct measurement can.
If your reflux is caused by low acid, taking an acid suppressor drops your acid output even further. Digestion slows down more. Bacteria start fermenting food in the stomach. Gas builds up. Pressure increases. The reflux continues or gets worse. You go back. The dose goes up. A second medication gets added. The real problem deepens with every step.
This isn't theoretical. Practitioners who work in this space see it all the time. People who've been on PPIs for years with symptoms that never resolved or gradually got worse. People who feel worse after meals despite being on maximum acid suppression. People who've been told they have refractory GERD when what they actually have is insufficient acid that looks identical to excess.
Standard workups for reflux don't measure how much acid your stomach is making. An endoscopy shows tissue damage but not acid levels. Esophageal pH monitoring measures acid exposure in the esophagus but doesn't tell you whether the stomach is producing too much or too little. PPI trials assume the diagnosis without confirming it.
The result is a gap. People with low acid and people with high acid present with the same symptom and get the same treatment. One group benefits. The other gets worse.
The Heidelberg test measures your acid output in real time. The bicarbonate challenge reveals whether your stomach can produce acid, how much it produces, and how quickly it bounces back. This directly answers the question that nothing else in the standard reflux workup addresses: is your stomach producing too much acid or too little?
For your practitioner, this turns a guess into a data-driven decision. For you, it can mean the difference between years of unnecessary suppression and a clear path toward actually resolving what's going on.
If you've been on acid-suppressing medication for months or years and your symptoms haven't improved or have gotten worse, a professional gastric acid assessment may give you the clarity you've been looking for. The test takes about an hour, requires no sedation, and you get your results the same day.
The Heidelberg pH Capsule is a Class I medical device, 510(k)-exempt, listed with the U.S. Food and Drug Administration under 21 CFR §876.1400. Listing of a device does not denote FDA approval, clearance, or endorsement.