Citric Acid
| Evidence Level: L4 | Predicted Indications: 8 |
Table of Contents
Citric Acid: From Dyspepsia to Stomach Disease
One-Sentence Summary
Citric acid (here in an effervescent citric acid/potassium bicarbonate tablet) is originally used for dyspepsia and headache disorder. The TxGNN model predicts it may be effective for stomach disease, but there are no registered clinical trials and the 19 publications retrieved are indirect, with none showing a therapeutic effect.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Dyspepsia and headache disorder (from the TxGNN knowledge graph; no approved indication text is available for the UK authorisation) |
| Predicted New Indication | Stomach disease |
| TxGNN Prediction Score | 99.74% |
| Evidence Level | L4 |
| UK Market Status | Marketed |
| Number of Marketing Authorisations | 1 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, citric acid is used in an effervescent combination with potassium bicarbonate, and it is already marketed for dyspepsia. A wider gastric indication is therefore biologically plausible.
The literature shows citric acid in the stomach mainly as a diagnostic adjunct. It is used as a test meal in the 13C-urea breath test for Helicobacter pylori, where it delays gastric emptying and increases urease contact. This is not a therapeutic effect. The other papers (ulcer diet, H. pylori physiology, cuproptosis in gastric cancer, veterinary cobalamin deficiency) are indirect or off-topic.
The high TxGNN score is partly explained by the overlap with the original dyspepsia indication. It should be read as a hypothesis, not as confirmation of benefit.
Other predicted indications were also reviewed. None has registered trials or therapeutic evidence:
- Rhinitis (L4): the strongest indirect signal is a citric acid/zwitterionic surfactant irrigation against Staphylococcus aureus biofilm in a sheep sinus model. Other papers use citric acid only as a cough trigger or taste-masking excipient.
- Pharyngitis (L4): citric acid is a cough-provoking irritant and may aggravate rather than treat airway symptoms.
- Acute laryngopharyngitis, postgastrectomy syndrome, nasal cavity disease, papillary conjunctivitis and blepharoconjunctivitis (L5): prediction only, with no supportive evidence. For airway and ocular conditions, the irritant properties of acid argue against benefit.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
None of the publications below tests citric acid as a treatment for stomach disease. Articles on cuproptosis, veterinary medicine, obesity devices, metabolomics and similar topics were judged off-topic and omitted.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 31204406 | 2019 | Diagnostic study | J Gastrointestin Liver Dis | Compared short (15 min) and standard (30 min) sampling for the 13C-urea breath test for H. pylori; citric acid is a variable in test protocols |
| 31505905 | 2019 | Diagnostic study | Gut Liver | Editorial-type commentary on whether a citric acid meal improves 13C-urea breath test accuracy in Asian populations |
| 30970440 | 2019 | Diagnostic study | Gut Liver | Evaluated the effect of citric acid on 13C-urea breath test accuracy after H. pylori eradication in a region with common atrophic gastritis |
| 15854177 | 2005 | Experimental | Aliment Pharmacol Ther | Compared citric, malic and ascorbic acids for effects on intragastric urease activity |
| 2072799 | 1991 | Review | Med Clin North Am | Diet in peptic ulcer disease; restrictive diets not supported, with only slight modifications advised |
| 9889978 | 1998 | Review | Adv Microb Physiol | Physiology and metabolism of H. pylori; background only |
| 35900644 | 2022 | Cohort | Metabolomics | High serum citric acid and L-carnitine detected in Koreans before gastric cancer onset; a biomarker finding, not a treatment |
| 7106518 | 1982 | Cohort | Gastroenterology | Salivary secretion in reflux oesophagitis; not about citric acid treatment |
UK Market Information
| Marketing Authorisation Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 0704030G0AAACAC (BNF-style product code; PL number not available) | Citric Acid/Pot Bicarb_Tab Eff | Effervescent tablet (per product name) | Not available |
Safety Considerations
- Contraindications (knowledge graph associations, not label text): the TxGNN knowledge graph links the drug with caution or contraindication in several conditions. The main groups are:
- Cardiovascular and renal: hypertension, congestive heart failure, kidney disease, impaired renal function, anuria.
- Adrenal: adrenal insufficiency, Addison disease, congenital adrenal hyperplasia.
- Gastrointestinal and hepatobiliary: peptic ulcer disease, chronic diarrhoeal disease, liver disease, gallbladder disease.
- Haematological: thrombocytopenia, haemophilia, anaemia.
- Metabolic and other: gout, hypercalcaemia, nephrocalcinosis, phosphorus metabolism disease, substance abuse/dependence.
- Drug Interactions: 15 interactions were identified.
- Major: aluminium hydroxide.
- Moderate: quinolone antibacterials, including ciprofloxacin, levofloxacin, moxifloxacin, ofloxacin, norfloxacin, enoxacin, gatifloxacin, gemifloxacin, lomefloxacin, nalidixic acid, cinoxacin, trovafloxacin, grepafloxacin and sparfloxacin.
Product-specific warnings and contraindications were not available. Please refer to the SmPC and BNF for authoritative safety information. Report suspected adverse reactions via the Yellow Card Scheme.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction rests on a model score and an overlap with the existing dyspepsia indication. There are no registered therapeutic trials, and the literature only describes citric acid as a diagnostic aid. This is a research question rather than an actionable repurposing candidate.
To proceed, the following is needed:
- Clarification of what “stomach disease” would mean clinically, and which specific condition (for example functional dyspepsia or reflux symptoms) would be the target beyond the current indication.
- The approved indication text, dosage form and PL number for the UK authorisation, plus SmPC warnings and contraindications.
- Mechanism of action data for the combination product.
- Controlled clinical evidence for a therapeutic gastric effect, beyond its use in breath-test protocols.
- A review of the quinolone and aluminium-containing antacid interactions before any extension of use.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.