Phenylephrine
| Evidence Level: L4 | Predicted Indications: 2 |
Table of Contents
- Phenylephrine
Phenylephrine: Nasal cavity disease
One-Sentence Summary
Phenylephrine is an alpha-1 adrenergic agonist used as a nasal decongestant and eye-drop vasoconstrictor/mydriatic. It is already used for conditions such as allergic rhinitis, the common cold and pharyngitis. The TxGNN model predicts it may be effective for nasal cavity disease, but there are no registered clinical trials and only 5 publications, mostly supportive or indirect. This prediction largely overlaps with existing indications rather than representing a truly new use.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Nasal cavity disease |
| TxGNN Prediction Score | 0.9997 |
| Evidence Level | L4 |
| Australia Market Status | Listed on the PBS Schedule (1 of 1 items) – TGA (ARTG) registration status is not included in this data |
| Number of PBS Items | 1 (valid: 1) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the data compiled for this report. Based on known pharmacology, phenylephrine is an alpha-1 adrenergic agonist. It constricts blood vessels in the nasal mucosa, which reduces congestion, swelling and mucosal bleeding.
The predicted indication, “nasal cavity disease”, is a broad category that already includes rhinitis, nasopharyngitis and the common cold, all existing indications for this drug. The very high TxGNN score (0.9997) probably reflects this closeness to established uses rather than a new therapeutic discovery.
The literature shows phenylephrine used in a combination nasal spray (Polydexa with phenylephrine) and as a vasoconstrictor in endoscopic sinus surgery. These are supportive uses, not controlled efficacy studies of phenylephrine alone.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 40899890 | 2025 | Experimental and clinical evaluation | Vestn Otorinolaringol | Safety and efficacy evaluation of Polydexa spray with phenylephrine in acute rhinosinusitis; aims to support wider use and reduce systemic antibiotic use |
| 37970776 | 2023 | Review | Vestn Otorinolaringol | Pathogenetic approach to inflammatory diseases of the nose and sinuses; therapy should reduce mucosal hyperaemia, swelling and mucus |
| 37184554 | 2023 | Clinical article | Vestn Otorinolaringol | Endoscopic assessment of the nasal mucosa after Polydexa spray with phenylephrine (dexamethasone, neomycin, polymyxin B, phenylephrine) |
| 25133491 | 2014 | RCT (triple blind) | PLoS One | Topical tranexamic acid and bleeding in endoscopic sinus surgery; phenylephrine is not the primary intervention |
| 7378007 | 1980 | Case report | Arch Ophthalmol | Toxic reactions to intranasal cocaine and phenylephrine before dacryocystorhinostomy; caution in hypertensive cardiovascular disease |
Australia Market Information
| ARTG Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 11908R | Prednefrin Forte | Eye drops containing prednisolone acetate 10 mg with phenylephrine hydrochloride 1.2 mg per mL, 10 mL | Not stated in the data compiled |
The only licensed product is an ophthalmic combination (prednisolone acetate plus phenylephrine). It is not a nasal formulation, so route compatibility with a nasal indication is unconfirmed.
Safety Considerations
- Contraindications (automated associations, not label text): hypertension/hypertensive disorder, liver failure and liver disease, kidney disease, epilepsy, COPD, peptic and gastric ulcer, pancreatitis, thrombocytopenia, adrenocortical insufficiency/Addison disease, hypothyroidism, inflammatory bowel disease, psychotic and other mental disorders, porphyria, and others. These likely reflect the corticosteroid component of the combination product as well as phenylephrine, and need verification against the Product Information.
- Drug Interactions: 180 interactions were identified, all of the 20 listed being Moderate. Main groups:
- Antidiabetic agents (e.g. acarbose, glimepiride, glipizide, glyburide, insulin, dapagliflozin, empagliflozin, exenatide)
- Anticholinergics (e.g. atropine ophthalmic, hyoscyamine, clidinium)
- Diethylpropion
- Literature caution: A case report describes toxicity with intranasal phenylephrine combined with cocaine, so use with other sympathomimetics or in hypertensive cardiovascular disease needs care.
Please refer to the TGA-approved Product Information (PI) for formal warnings, as label-based warnings were not available.
Conclusion and Next Steps
Decision: Hold
Rationale: The predicted indication overlaps heavily with existing rhinitis and nasopharyngitis uses, so it is not a clearly novel repurposing. There are no registered trials, and the supporting literature is mostly combination-product, surgical-adjunct or indirect. The Australian product is an ophthalmic eye drop, not a nasal formulation.
To proceed, the following is needed:
- Mechanism of action data
- TGA Product Information warnings and contraindications for safety screening
- Controlled studies of phenylephrine alone in a defined nasal condition
- Confirmation of a suitable nasal formulation and route in Australia
- Clarification of which nasal cavity conditions are genuinely new compared with existing indications
Other Predictions (for reference)
| Predicted Indication | TxGNN Score | Evidence Level | Decision |
|---|---|---|---|
| Trigeminal autonomic cephalalgia | 0.9930 | L4 | Hold (literature uses phenylephrine only as a diagnostic pupillometry probe, not as a treatment; no therapeutic evidence) |
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.