HOW WE'RE DIFFERENT

Most tests guess. We measure.

Patients with persistent digestive symptoms often go through multiple tests that look at structure, blood markers, or transit time. None of them measure how much acid your stomach is actually producing, or how quickly it recovers after a challenge. That is what makes the Heidelberg test different. Here is how it compares to every other method available.

Method
What it measures
Key limitations
Real-time?
Heidelberg pH Capsule
Gastric pH and reacidification capacity via bicarbonate challenge
Requires practitioner visit; not yet widely available
Yes
OTHER METHODS
Upper endoscopy with biopsy
Visual inspection of stomach lining and tissue structure
Shows structure, not function. A normal scope does not mean normal acid.
No
Bravo pH Capsule
pH in the esophagus over 2 to 4 days
Measures reflux in the esophagus, not acid production in the stomach
Esophageal only
SmartPill
Transit time and pH through the entire GI tract
Passive transit. No challenge protocol. No longer commercially available.
No
Serum pepsinogen / gastrin
Blood markers that suggest cell damage or gastric stress
Indirect. Shows damage, not how much acid you are making right now.
No
Nasogastric aspiration
Acid collected through a tube in the nose
Invasive. Uncomfortable. Largely abandoned in clinical practice.
No
Baking soda challenge
You time a burp
No data. No measurement. Not clinically validated.
No
Betaine HCl challenge
You swallow acid and see if you feel warmth
No quantitative data. Subjective. Unreliable.
No

Every other method on this list measures something around stomach acid: the structure of the lining, markers in the blood, acid in the wrong place, or a subjective feeling. The Heidelberg test is the only commercially available method that measures gastric acid secretion itself, in real time, through a standardized challenge protocol.

No other test gives you this answer.

Now find out if you need it.

HEIDELBERG

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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.

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