RESEARCH

The Research Behind the Test

The Heidelberg pH Capsule has been used in peer-reviewed research since 1960. More than 140 indexed publications span six decades, covering device validation, gastric acid physiology, pharmacokinetics, drug development, nutrient absorption, and clinical diagnostics. The research spans institutions including the University of Heidelberg, the University of Michigan, UCSF, Thomas Jefferson University, and the University of Vienna, and includes pharmaceutical research by Pfizer, Merck, Genentech, GlaxoSmithKline, CIBA-Geigy, and Bristol Myers Squibb.

Research by category

Device Validation and Methodology
35 Studies
Pharmacokinetics and Drug Development
30 studies
Hypochlorhydria and Achlorhydria
9 studies
Gastric Acid Physiology and Hyperchlorhydria
11 studies
PPI and H2-Blocker Effects
8 studies
Aging and Elderly Gastric Function
3 studies
Pediatric and Cystic Fibrosis
2 studies
Bariatric and Post-Surgical
6 studies
Nutrient Absorption
3 studies
Animal Studies
8 studies
Historical Reviews and Citing Works
27 studies

Landmark studies

1. Dressman et al. 1990 — established reference gastric pH values still used in pharmaceutical modeling today
2. Russell et al. 1993 — definitive elderly gastric pH dataset, dispelled the myth of universal age-related achlorhydria
3. Mojaverian et al. 1985 — validated the capsule as a marker of gastric motility
4. Yarbrough et al. 1969 — landmark US surgical validation establishing tubeless gastric analysis
5. Yago et al. 2014 — demonstrated betaine HCl can rescue drug absorption in PPI-induced hypochlorhydria (Genentech/UCSF)
6. Liszt et al. 2017 — identified bitter-taste receptor mechanisms for gastric acid secretion (published in PNAS)
7. Ewe & Weis 1968 — 533-patient correlation between Heidelberg findings and gastric biopsy histology
8. Surofchy et al. 2019 — most recent UCSF randomized controlled trial using the Heidelberg system

The complete annotated bibliography with full citations and PubMed links is available on heidelbergmed.com.

Six decades of evidence. One measurement.

See if the Heidelberg test is your next step.

HEIDELBERG

Est. 1964
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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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