Phenylpropanolamine
| Evidence Level: L5 | Predicted Indications: 4 |
Table of Contents
Phenylpropanolamine: Nasal cavity disease
One-Sentence Summary
Phenylpropanolamine is a sympathomimetic decongestant, originally used for allergic rhinitis, the common cold and related upper airway and conjunctival conditions. The TxGNN model predicts it may be effective for nasal cavity disease, but the support is thin: no registered clinical trials and only 3 publications (one comparative clinical pharmacology study and two preclinical animal studies). Its serious safety history (hemorrhagic stroke risk) calls for strong caution.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Nasal cavity disease |
| TxGNN Prediction Score | 0.9998 |
| Evidence Level | L5 |
| India Market Status | Listed in a compiled Indian medicine price dataset (at least 20) – CDSCO approval status is not included in this data |
| Number of Listed Products | at least 20 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the compiled data. Based on known pharmacology, phenylpropanolamine is a direct- and indirect-acting sympathomimetic. It causes alpha-adrenergic vasoconstriction of nasal mucosal blood vessels, which reduces swelling and congestion.
Its original indications (allergic and vasomotor rhinitis, nasopharyngitis, the common cold) are largely nasal conditions. “Nasal cavity disease” is a broad category that overlaps heavily with them, so this prediction looks more like a natural extension of existing use than a truly new indication. The mechanism, reducing mucosal congestion, would plausibly apply across this category.
The other predictions are weaker:
- Acute laryngopharyngitis (0.9998) is a close extension of the existing pharyngitis indications, supported only by the model.
- Rosacea conjunctivitis (0.9919) could theoretically benefit from reduced redness, but its cause (chronic inflammation, meibomian gland dysfunction) is not addressed by a decongestant.
- Faucial diphtheria (0.9908) and cervical disc degenerative disorder (0.9903) have no plausible mechanistic link. Their scores come from the TxGNN model (deep learning) and may reflect similarities the model learned between related diseases, not biological evidence.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 11345158 | 2001 | Comparative clinical pharmacology study | American Journal of Rhinology | Compared the oral and topical decongestant effects of phenylpropanolamine and d-pseudoephedrine, using acoustic rhinometry to measure changes in nasal cavity dimensions. |
| 10582118 | 1999 | Preclinical (animal) | American Journal of Rhinology | Combined histamine H1 and H3 receptor blockade produced nasal decongestion in a cat model of nasal congestion. |
| 10582116 | 1999 | Preclinical (animal) | American Journal of Rhinology | Described pressure and acoustic rhinometry for measuring nasal patency in a feline congestion model. |
India Market Information
All 20 registrations are valid single-ingredient licences. The data contain no approved-indication text. The main authorizations are listed below.
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 62698 | Dexovik Syrup | Syrup, 100 ml bottle | Not stated |
| 223808 | Tussiz P Syrup | Syrup, 60 ml bottle | Not stated |
| 219285 | Triatussic 12.5 mg/2 mg/10 mg Tablet | Tablet, strip of 10 | Not stated |
| 46398 | Chericold Capsule | Capsule, strip of 10 | Not stated |
| 223840 | Tritus Plus Suspension | Suspension, 50 ml bottle | Not stated |
Safety Considerations
- Cardiovascular and stroke risk: Phenylpropanolamine has been withdrawn or restricted in many markets because of hemorrhagic stroke risk. Any repurposing would need strong guardrails.
- Disease associations flagged in the knowledge graph (not label text): hypertension and hypotensive disorders, liver failure and liver disease, kidney disease, epilepsy, insomnia, COPD, pancreatitis, gallbladder disease, thrombocytopenia, hypothyroidism, peptic ulcer disease, inflammatory bowel disease, benign prostatic hyperplasia, gout, substance abuse/dependence, and several blood and iron-metabolism disorders (sickle cell anemia, hemophilia, hemochromatosis, Wilson disease).
- Drug interactions: 176 interactions were identified. Major-level ones include bupropion, lorcaserin, diethylpropion and phentermine. Moderate-level ones include epinephrine, isometheptene, and several antidiabetic drugs (e.g., metformin, pioglitazone, empagliflozin, dapagliflozin, repaglinide, acarbose).
Package insert warnings and contraindications were not available, so please refer to the package insert for full safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The evidence is limited to one comparative pharmacology study and two animal studies, with no registered clinical trials. The nasal cavity prediction largely overlaps with existing rhinitis indications. The drug’s stroke and cardiovascular risks are a major concern.
To proceed, the following is needed:
- Mechanism of action data
- Package insert warnings and contraindications for the India-marketed products
- Controlled clinical trial data in nasal cavity disease
- A benefit-risk assessment focused on hemorrhagic stroke and blood pressure effects, with a plan for excluding high-risk patients
- Approved indication text for the India licences, to clarify how far the prediction goes beyond current use
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.