Sulfamethoxazole
| Evidence Level: L5 | Predicted Indications: 1 |
Table of Contents
Sulfamethoxazole: Acute contagious conjunctivitis
One-Sentence Summary
Sulfamethoxazole is a sulfonamide antibacterial, originally used for infections such as otitis media, nocardiosis, toxoplasmosis, pneumocystosis, shigellosis and conjunctivitis. The TxGNN model predicts it may be effective for acute contagious conjunctivitis, but conjunctivitis already appears among its original indications, so this is not a true repurposing candidate. Support is limited to 0 clinical trials and 1 publication (a cohort study of bacterial conjunctivitis).
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Acute contagious conjunctivitis |
| TxGNN Prediction Score | 0.9963 |
| 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 data compiled for this report. Based on general pharmacology, sulfamethoxazole inhibits bacterial dihydropteroate synthase and blocks folate synthesis. It is usually combined with trimethoprim, which blocks the folate pathway at a second step. This sequential blockade is plausibly relevant to bacterial conjunctivitis, an infection caused by susceptible pathogens.
Importantly, conjunctivitis is already listed among the drug’s original indications. The high TxGNN score (0.9963) is therefore likely driven by this existing association rather than by a genuinely new finding. The mechanism link above is inferred from general knowledge, not from the supplied data.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 31788487 | 2019 | Cohort (retrospective) | Medical Hypothesis, Discovery & Innovation Ophthalmology Journal | Bacteriology and antibiotic susceptibility patterns in childhood acute bacterial conjunctivitis in Western Greece. It describes the pathogens and susceptibility in a paediatric hospital and does not evaluate sulfamethoxazole efficacy directly. |
India Market Information
Twenty valid single-ingredient registrations are on record, with no cancelled licences. Approved-indication text is not recorded for any of them. The five main registrations are listed below.
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 54981 | Cidaprim Forte Oral Suspension | Bottle of 50 ml oral suspension | Not recorded |
| 201573 | Synastat 800mg/160mg Tablet | Strip of 10 tablets | Not recorded |
| 30976 | Bioprim 800mg/160mg Tablet | Strip of 10 tablets | Not recorded |
| 25959 | Bactrim Syrup (Abbott) | Bottle of 50 ml syrup | Not recorded |
| 199546 | Septran DS 800mg/160mg Tablet | Strip of 10 tablets | Not recorded |
Available forms are oral tablets, suspensions, syrups and paediatric drops. No ophthalmic (eye-drop) formulation is listed.
Safety Considerations
Contraindications / risk conditions (from the knowledge graph, not label text): inherited porphyria and other porphyrin metabolism diseases, kidney disease and kidney failure, uraemia, glomerulonephritis, liver disease, gallbladder disease, thrombocytopenia, neutropenia, agranulocytosis, G6PD deficiency, folic acid deficiency anaemia, Clostridium difficile colitis, perinatal necrotizing enterocolitis, glycogen storage disease, cystinuria, galactosaemia and pyoureter.
Drug Interactions: 151 interactions are recorded. Examples are listed below.
- Moderate: sulfonylurea antidiabetics (chlorpropamide, glimepiride, glipizide, glyburide, acetohexamide); insulins (human, aspart, degludec, detemir, glargine, glulisine); balsalazide; picosulfuric acid. These mainly involve hypoglycaemia risk with antidiabetics.
- Minor: famotidine, clarithromycin, cisapride, and the setrons dolasetron, granisetron and palonosetron.
Package insert warnings and contraindications were not available for this report. Please refer to the package insert for the approved safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: Conjunctivitis is already an original indication, so this is not a true repurposing opportunity. The evidence is model prediction plus one descriptive cohort study, with no clinical trials (Evidence Level L4). Package insert safety data are also missing, which blocks safety screening.
To proceed, the following is needed:
- Obtain the package insert warnings and contraindications from the Indian regulatory source to complete safety screening.
- Obtain mechanism of action data from DrugBank.
- Confirm whether a distinct new indication (for example a specific subtype of contagious conjunctivitis or a topical route) is intended. If so, the route would need to be assessed, since only oral and systemic forms are marketed in India.
- Identify clinical studies of sulfamethoxazole (or trimethoprim-sulfamethoxazole) in conjunctivitis, and weigh them against current topical antibiotic standards of care and local resistance patterns.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.