Guaifenesin
| Evidence Level: L3 | Predicted Indications: 10 |
Table of Contents
Guaifenesin: From Expectorant Use to Nasal Cavity Disease
One-Sentence Summary
Guaifenesin is a marketed expectorant used to loosen airway mucus. The TxGNN model predicts it may be effective for nasal cavity disease, with a direct signal in pediatric chronic rhinitis. Support is limited: 1 completed Phase 2 pilot trial and 2 review-type publications, with no results supplied.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not stated in the supplied SAHPRA records; known use is as an expectorant |
| Predicted New Indication | Nasal cavity disease |
| TxGNN Prediction Score | 99.98% |
| Evidence Level | L3 |
| South Africa Market Status | Marketed |
| Number of SAHPRA Registrations | 8 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on general pharmacology, guaifenesin is an expectorant thought to thin and mobilise airway mucus. Its established use is in respiratory mucus conditions, and mechanistically it may be applicable to mucus-related upper-airway disease such as chronic rhinitis.
The link between the original and predicted indications is anatomical and functional. Both involve mucus and secretion clearance along the respiratory tract. Supporting evidence for the biology comes from a laboratory study of guaifenesin on MUC5AC (a mucus protein) and mucociliary transport in human tracheal-bronchial cells (PMID 23113953). This is indirect, in vitro, and not nasal, so it cannot show clinical benefit in nasal disease.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT01364467 | Phase 2 | Completed | 30 | 14-day placebo-controlled pilot of oral guaifenesin in children aged 7–18 with chronic rhinitis. It compares symptom scores (SN-5) with nasal airway volume and nasal secretion properties. No outcome data were supplied. |
The registry description mentions 36 children, while listed enrollment is 30. Randomisation details and results should be verified.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 9065342 | 1997 | Review | American Journal of Rhinology | Management of sinusitis in 22 adults with cystic fibrosis. It offers general management recommendations and does not test guaifenesin as a treatment. |
| 12487405 | 2002 | Review | Logopedics, Phoniatrics, Vocology | Treatment of respiratory allergies in voice users. It notes that decongestants combined with guaifenesin may be useful, which is an expert opinion rather than trial evidence. |
South Africa Market Information
Approved indication text was not included in the supplied records. Five of the 8 registrations are listed below.
| Registration Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| Reg. No. Y/10.1.1/139 | Merck-Expectorant | Syrup | Not stated in supplied record |
| Reg. No. 27/10.1/0485 | Adco-neofed paed | Syrup | Not stated in supplied record |
| Reg. No. Y/10.1/140 | Merck-Paed Expectorant | Syrup | Not stated in supplied record |
| Reg. No. G1032 (OM) | Corbar linctus | Syrup | Not stated in supplied record |
| Reg. No. 27/10.1/0537 | Trifen expect adult | Syrup | Not stated in supplied record |
Safety Considerations
Please refer to the SAHPRA-approved Professional Information (PI) for safety information. Report adverse drug reactions to SAHPRA.
Conclusion and Next Steps
Decision: Hold
Rationale: The only direct evidence is one small, completed Phase 2 pilot in children with chronic rhinitis. Its design and results are not confirmed, so the evidence stays at L3 rather than L2. The high TxGNN score is a computational prediction and not clinical proof. Safety information has not yet been reviewed.
To proceed, the following is needed:
- Results and design details (randomisation, control arm, outcomes) for NCT01364467, or a publication from it. A positive randomised result would support upgrading to L2.
- SAHPRA package insert warnings and contraindications, which must be reviewed before any safety screening.
- Curated mechanism of action data from DrugBank.
- Approved indication text for the registered South African products.
The other nine predictions are weaker. Tracheal disease reaches L4 on in vitro data only. The remaining eight are L5, with no trial or literature support, and are also on Hold.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.