Acetic Acid
| Evidence Level: L5 | Predicted Indications: 9 |
Table of Contents
Acetic Acid: From Otitis Externa to Post-Bacterial Disorder
One-Sentence Summary
Acetic acid (marketed in New Zealand as Aci-Jel) was originally used for otitis externa and other external ear conditions. The TxGNN model predicts it may be effective for post-bacterial disorder, but no clinical trials and no publications currently support this prediction. It is a computational prediction only.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Otitis externa; external ear disease (from the knowledge graph; no approved indication text on the New Zealand licence) |
| Predicted New Indication | Post-bacterial disorder |
| TxGNN Prediction Score | 99.98% |
| Evidence Level | L5 |
| New Zealand Market Status | ✓ Marketed |
| Number of Authorizations | 1 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, acetic acid is a topical antibacterial and antiseptic agent. Its activity in ear infections is generally attributed to acidification and disruption of microbial cell function. Mechanistically, this could apply to some infection-related conditions.
However, the link to post-bacterial disorders is weak. Such conditions are generally immune-mediated or post-inflammatory sequelae rather than active local infections, so a topical acidifying antiseptic has no clear route to treat them. The very high score most likely reflects graph proximity to infection-related terms rather than a real therapeutic signal.
For context, the other top predictions (postinfectious vasculitis, post-infectious syndrome, Chagas cardiomyopathy, infective urethral stricture, infection-related haemolytic uraemic syndrome, drug-induced osteoporosis) also have no clinical evidence and no plausible mechanism for a topical agent. The only prediction with some supporting literature is tinea corporis (score 99.25%, evidence level L4, "Research Question" status). This is a secondary signal worth noting:
- Historical reports from 1946–1958 describe dilute or increasing concentrations of acetic acid used for tinea capitis and foot epidermophytosis.
- In vitro and chemical-peeling reports give indirect support for antifungal use against dermatophytes.
- These sources are old, uncontrolled or laboratory-based, and concern related dermatophytoses rather than tinea corporis itself.
Clinical Trial Evidence
Currently no related clinical trials registered for post-bacterial disorder. None are registered for the other top-ranked predictions, including tinea corporis.
Literature Evidence
No literature is available for post-bacterial disorder. The literature below relates to other predicted indications and is shown for context only.
Post-infectious syndrome (rank 3):
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 20848144 | 2011 | Review | Journal of Gastroenterology | Systematic review of animal models of post-infectious irritable bowel syndrome. It does not evaluate acetic acid as a treatment, so it is not supporting evidence |
Tinea corporis (rank 9), most relevant items:
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 31049344 | 2019 | Clinical report/Review | Skin Appendage Disorders | Chemical peeling as an alternative to oral antifungals for onychomycosis in patients where oral drugs are unsuitable |
| 26857689 | 2016 | In vitro study | Mycoses | Topical antifungal products compared in an in vitro onychomycosis model against Trichophyton mentagrophytes |
| 37256034 | 2023 | Case series (safety) | Archives of Plastic Surgery | Burns caused by Korean folk remedies; a safety signal for uncontrolled topical acid-based remedies |
| 20256868 | 1947 | Historical clinical series | Urologic and Cutaneous Review | Tinea capitis treated with special iodine and dilute acetic acid in a larger patient series |
| 20996178 | 1946 | Historical clinical report | JAMA | Tinea capitis treated with special iodine and dilute acetic acid |
| 20983383 | 1946 | Historical clinical report | Archives of Dermatology and Syphilology | Treatment of tinea capitis with special iodine and dilute acetic acid |
| 13616002 | 1958 | Historical clinical report | Vestnik Dermatologii i Venerologii | Foot epidermophytosis treated with increasing concentrations of acetic acid |
New Zealand Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 536962 | Aci-Jel | Jelly (glacial acetic acid 0.94%, hydroxyquinoline sulphate 0.025%, glycerol 5%, ricinoleic acid 0.75%) with applicator | Not stated in the data compiled for this report |
Safety Considerations
- Disease-level contraindication signals (knowledge graph, not label text): inherited porphyria, porphyrin metabolism disease, porphyria, herpes simplex infection, geniculate herpes zoster.
- Safety signal for topical acid use: a 2023 case series describes burns from folk remedies, which indicates a risk of tissue injury with uncontrolled use of acid-based topical products.
- Drug interactions: no interactions were found in the queried data.
Please refer to the package insert for warnings and contraindications, as label-based safety text was not available for this report.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction for post-bacterial disorder rests on a model score alone (evidence level L5), with no trials, no literature and no plausible mechanism for a topical antiseptic. Acetic acid is marketed in New Zealand as a single-ingredient licence, but this does not support the new indication. Of the predicted indications, only tinea corporis has indirect, low-quality support, and it warrants a research question rather than a recommendation.
To proceed, the following is needed:
- The Medsafe package insert (warnings, contraindications and approved indications), which is a blocking gap for safety screening
- Mechanism of action data from DrugBank
- A clear mechanistic rationale for post-bacterial disorder, or a shift in focus to tinea corporis
- For tinea corporis, modern controlled studies of dermatophyte efficacy, with tolerability and skin-injury safety assessment
- Route and formulation compatibility assessment, since the current product is a gel with an applicator and not designed for skin or systemic use
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.