Phenylephrine

證據等級: L5

預測適應症: 3 個

Phenylephrine: From Decongestant/Vasoconstrictor Use to Nasal Cavity Disease

One-Sentence Summary

Phenylephrine is a well-established α1-adrenergic agonist used as a nasal/topical decongestant and vasoconstrictor (referenced across the evidence base as “Neo-Synephrine” and as a component of combination nasal sprays such as Co-phenylcaine and Polydexa). The TxGNN model predicts it may be effective for Nasal Cavity Disease, with 8 clinical trials and 8 publications currently identified in the surrounding evidence space, though none directly establish phenylephrine monotherapy as a treatment for this indication. No SAHPRA-approved Professional Information (PI) is currently available for this product.

Quick Overview

Item	Content
Original Indication	Not available — no SAHPRA-registered indication text (drug not marketed in South Africa); commonly known decongestant/vasoconstrictor use referenced in evidence
Predicted New Indication	Nasal Cavity Disease
TxGNN Prediction Score	99.97%
Evidence Level	L3
South Africa Market Status	Not marketed
Number of SAHPRA Registrations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data is not available. Based on known information, phenylephrine is a selective α1-adrenergic receptor agonist that produces vasoconstriction of nasal mucosal blood vessels — this pharmacological role is corroborated repeatedly in the collected evidence, including its use as “Neo-Synephrine” hydrochloride administered intranasally, its inclusion in the combination product Co-phenylcaine (used for nasal decongestion and local anaesthesia before nasoendoscopy), and in Polydexa nasal spray for rhinosinusitis.

The predicted new indication, “nasal cavity disease,” is mechanistically adjacent to phenylephrine’s known decongestant/vasoconstrictor action rather than a truly novel pharmacological application. The surrounding clinical trial and literature evidence largely involves phenylephrine-containing combination products used peri-procedurally (endoscopy, sinus surgery, dacryocystorhinostomy) or in rhinosinusitis management, supporting biological plausibility, but no identified study isolates phenylephrine as monotherapy with a primary endpoint of treating “nasal cavity disease” as a defined condition. The mechanistic rationale is therefore reasonable but the direct evidentiary link remains indirect.

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT00562120	Phase 2	Completed	21	H3-receptor antagonist tested against nasal allergen challenge-induced congestion in seasonal allergic rhinitis; acoustic rhinometry used to measure congestion (not a phenylephrine trial).
NCT03380715	NA	Completed	106	Co-phenylcaine (contains phenylephrine) nasal spray vs. nasal nebulization compared prior to rigid nasoendoscopy for decongestion/anaesthesia.
NCT06443255	Phase 3	Completed	16	Triple crossover comparing cocaine, lidocaine/xylometazoline, and saline for intranasal analgesia before awake nasotracheal intubation.
NCT02993770	NA	Unknown	120	Endonasal-endoscopic vs. external dacryocystorhinostomy for nasolacrimal duct obstruction.
NCT03228914	Phase 4	Completed	20	Topical oxymetazoline vs. epinephrine compared for blood loss/visualization before endoscopic sinus surgery.
NCT03962634	Phase 2	Terminated	3	Kovanaze (phenylephrine/tetracaine) nasal mist vs. articaine injection for maxillary pulpal anaesthesia.
NCT06457100	Phase 1/2	Active, not recruiting	60	Perioperative esmolol vs. lidocaine infusion for recovery quality after functional endoscopic sinus surgery.
NCT04104789	Phase 2	Withdrawn	0	Kovanaze nasal mist vs. articaine for maxillary pulpal anaesthesia (same design as NCT03962634, withdrawn before enrollment).

None of the above trials evaluate phenylephrine monotherapy for a defined “nasal cavity disease” diagnosis; most involve phenylephrine-containing combination products used peri-procedurally.

Literature Evidence

PMID	Year	Type	Journal	Key Findings
25133491	2014	RCT	PLoS One	Triple-blind RCT of topical tranexamic acid on bleeding/surgical field quality during FESS in chronic rhinosinusitis.
15854186	2005	RCT	Int J Clin Pract	Double-blind RCT of cophenylcaine spray (contains phenylephrine) vs. placebo before flexible nasendoscopy; minimal pain/discomfort in both arms.
40899890	2025	Clinical evaluation	Vestnik otorinolaringologii	Experimental and clinical safety/efficacy evaluation of Polydexa spray with phenylephrine in acute rhinosinusitis.
37184554	2023	Case-based/diagnostic	Vestnik otorinolaringologii	Endoscopic assessment of nasal mucosa after topical therapy including Polydexa with phenylephrine, in granulomatosis with polyangiitis.
37970776	2023	Review	Vestnik otorinolaringologii	Review of pathogenetic approach to treating inflammatory diseases of the nose and paranasal sinuses.
9780066	1998	Observational	Int J Pediatr Otorhinolaryngol	Acoustic rhinometric evaluation of nasal cavity/nasopharynx after adenoidectomy/tonsillectomy.
1375136	1992	In vitro study	Clin Otolaryngol Allied Sci	Preliminary in vitro study of drug effects, including sympathomimetics, on nasal ciliary beat frequency.
7378007	1980	Case report	Arch Ophthalmol	Cocaine toxicity during dacryocystorhinostomy; one patient also reacted to intranasal phenylephrine (Neo-Synephrine).

South Africa Market Information

Phenylephrine currently has no SAHPRA product registration on file in this evidence pack (0 registrations), and market status is recorded as not marketed. No product/dosage form/indication data is available to tabulate.

Safety Considerations

Please refer to the SAHPRA-approved Professional Information (PI) for safety information. Report adverse drug reactions to SAHPRA.

Note: one case report in the literature evidence (PMID 7378007) describes a toxic reaction to intranasal phenylephrine when combined with cocaine, attributed to phenylephrine’s sympathomimetic/α1-agonist effect — relevant context for any future cardiovascular or drug-interaction assessment, but not a substitute for formal PI review.

Other TxGNN-Predicted Indications (Lower Priority)

Rank	Disease	TxGNN Score	Evidence	Decision
2	Acute laryngopharyngitis	99.97%	No trials or literature identified	Hold (L5 — mechanistic hypothesis only)
3	Trigeminal autonomic cephalalgia	99.30%	No trials or literature identified	Hold (L5 — mechanistic hypothesis only)

Both are supported only by theoretical extension of phenylephrine’s α1-agonist vasoconstrictive mechanism, with no clinical trial or literature evidence identified in this data cutoff.

Conclusion and Next Steps

Decision: Hold

Rationale:

The Professional Information / safety warnings data gap (DG001) is classified as Blocking, meaning safety pre-assessment (S1) cannot proceed until PI data is obtained.
Phenylephrine is not currently marketed or SAHPRA-registered in South Africa (0 registrations), and no direct RCT evidence establishes phenylephrine monotherapy for “nasal cavity disease” — existing evidence involves combination products used peri-procedurally.

To proceed, the following is needed:

Resolve DG001: obtain SAHPRA-approved PI (warnings, contraindications) before any safety evaluation
Resolve DG002: obtain detailed mechanism-of-action documentation from DrugBank/other sources
Confirm South African market/registration pathway and available routes of administration
Classify pending trial/literature relevance grades and study types to refine the evidence level
Identify or commission studies isolating phenylephrine (not combination products) for the specific nasal cavity disease indication
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.