Astemizole
| Evidence Level: L5 | Predicted Indications: 1 |
Table of Contents
Astemizole: From Allergic Rhinitis to Rosacea Conjunctivitis
One-Sentence Summary
Astemizole is a second-generation H1-receptor antagonist, originally used for allergic rhinitis, allergic and atopic conjunctivitis, and idiopathic urticaria. The TxGNN model predicts it may be effective for rosacea conjunctivitis, but currently no clinical trials and no publications support this direction, so the prediction rests on model output alone.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Allergic rhinitis (also vasomotor rhinitis, atopic, papillary and vernal conjunctivitis, idiopathic urticaria) |
| Predicted New Indication | Rosacea conjunctivitis |
| TxGNN Prediction Score | 0.9978 |
| Evidence Level | L5 |
| India Market Status | Listed in a compiled Indian medicine price dataset (9 of 9) – CDSCO approval status is not included in this data |
| Number of Listed Products | 9 (valid: 9) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, astemizole is a second-generation H1-receptor antagonist. Its efficacy in allergic and atopic conjunctivitis (including vernal and papillary forms) is established, and by blocking histamine it may mechanistically reduce histamine-mediated inflammation of the ocular surface in rosacea conjunctivitis.
This link is weak, however. Ocular rosacea is driven mainly by meibomian gland dysfunction, tear film instability, microbial and Demodex factors, and innate immune activation. Histamine plays only a minor role. The very high TxGNN score (0.9978) most likely reflects network proximity to astemizole’s existing conjunctivitis indications rather than an independent mechanistic signal. Because the mechanism data is missing, the link is inferred from the drug class only.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
Currently no related literature available.
India Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 6296 | Acemiz Plus 5mg Suspension (Lupin Ltd) | Bottle of 60 ml suspension | Not stated |
| 6237 | Astem 10mg Tablet (Medley Pharmaceuticals) | Strip of 10 tablets | Not stated |
| 11004 | Astelong 5mg Oral Suspension (Torrent Pharmaceuticals Ltd) | Bottle of 60 ml oral suspension | Not stated |
| 202130 | Stemiz 10mg Tablet (Zydus Cadila) | Strip of 10 tablets | Not stated |
| 6542 | Alestol 10mg Tablet (Indico Pharmaceuticals) | Strip of 10 tablets | Not stated |
Nine valid single-ingredient registrations exist in total; the five main ones are listed above. All are oral tablets or suspensions, and no ophthalmic formulation appears in the data compiled for this report.
Safety Considerations
- Cardiac risk: Astemizole was withdrawn from many markets because of hERG channel blockade, QT prolongation and torsades de pointes risk. This weighs heavily against any new use.
- Drug Interactions: 276 interactions are recorded, notably with CYP3A4 inhibitors. Major-level interactions include:
- Cimetidine
- Clarithromycin
- Aprepitant
- Dolasetron
- Miconazole
- Picosulfuric acid
- Sodium sulfate
- Polyethylene glycol (3350 with electrolytes)
Moderate-level interactions include famotidine, loperamide, ondansetron, palonosetron, levofloxacin, lactulose and lactitol.
Package insert warnings and contraindications were not available; please refer to the package insert for further safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction has no supporting clinical trials or literature (Evidence Level L5), and the mechanistic link to rosacea conjunctivitis is weak. The serious cardiac safety profile (QT prolongation, torsades de pointes) and extensive interaction burden make a new use hard to justify without much stronger evidence.
To proceed, the following is needed:
- Package insert warnings and contraindications from the Indian regulatory source (needed for safety screening)
- Detailed mechanism of action data
- Preclinical or clinical evidence that H1 blockade benefits ocular rosacea
- A comparison against existing safer antihistamines and standard ocular rosacea therapies
- A cardiac safety risk-benefit assessment, including a route-compatibility check (for example, whether a topical ocular formulation could limit systemic exposure)
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.