Cyclopentolate
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Cyclopentolate: From Cycloplegia to Cauda Equina Syndrome
One-Sentence Summary
Cyclopentolate is a topical antimuscarinic eye drop, originally used to paralyse the eye's focusing muscle (cycloplegia) and dilate the pupil. The TxGNN model's top-ranked prediction is cauda equina syndrome, but this is a model prediction only, with 0 clinical trials and 0 publications supporting it. The only predicted indications with any published literature are eye-related (uveitis, iris disease, ciliary body disease), and even there the evidence is indirect, with no registered trials.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Cycloplegia (the approved indication text on the Singapore licence is blank) |
| Predicted New Indication | Cauda equina syndrome |
| TxGNN Prediction Score | 99.54% |
| Evidence Level | L5 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 1 |
| Recommended Decision | Hold |
For reference, the other highest-ranked predictions are neurogenic bladder (99.40%), irritable bowel syndrome (99.27%), acute laryngopharyngitis (97.69%), pharyngitis (97.59%) and nasal cavity disease (97.56%), all L5 and Hold. The eye-related predictions, uveitis (95.73%), iris disease (94.36%), panuveitis (93.38%) and ciliary body disease (93.30%), are the only ones with literature (L4). Uveitis, iris disease and ciliary body disease are rated "Research Question", and panuveitis is rated "Hold".
Why is This Prediction Reasonable?
Detailed mechanism of action data is not currently available. Based on known pharmacology, cyclopentolate is a muscarinic receptor antagonist. Its efficacy in cycloplegia is established, and mechanistically it may be applicable to conditions in which muscarinic blockade is useful.
Top prediction (cauda equina syndrome): The only plausible link is antimuscarinic modulation of bladder and bowel function after neurogenic dysfunction. However, cauda equina syndrome is a surgical emergency caused by nerve root compression, which an anticholinergic cannot treat. Cyclopentolate has no documented systemic use for this condition, so this prediction is weak.
Other non-ocular predictions: Class-level rationales exist for neurogenic bladder (e.g. oxybutynin), irritable bowel syndrome (e.g. hyoscine, dicyclomine) and rhinorrhoea (e.g. ipratropium). No cyclopentolate-specific data exist. Its ophthalmic-only formulation and the risk of central nervous system toxicity with systemic exposure make these uses impractical. The neurogenic bladder term is also flagged as obsolete in the ontology. The links to laryngopharyngitis and pharyngitis rest only on a nonspecific antisecretory effect.
Eye-related predictions: These are the most biologically coherent.
- Uveitis: Cycloplegics and mydriatics are established adjuncts in anterior uveitis. They relieve ciliary spasm and pain and prevent posterior synechiae. They are symptomatic rather than disease-modifying, and longer-acting agents such as atropine or homatropine are usually preferred in active inflammation.
- Iris disease and ciliary body disease: Cyclopentolate acts directly on the iris sphincter and ciliary muscle. The literature shows pharmacodynamic and diagnostic use and safety findings, not therapeutic benefit.
- Panuveitis: Cycloplegia could help only with the anterior component. Treatment relies mainly on corticosteroids and immunomodulators.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
No literature is available for the top-ranked prediction (cauda equina syndrome). The table below shows selected publications for the best-supported eye-related predictions. Most are case reports, drug-induced eye toxicity reports or cohort studies, so none constitutes direct efficacy evidence.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 29606019 | 2018 | RCT | Cutan Ocul Toxicol | Topical atropine with or without intracameral epinephrine for preventing intraoperative floppy iris syndrome (iris disease; not cyclopentolate-specific) |
| 36411874 | 2022 | Review | Clin Ophthalmol | Mini review of the benefits and risks of ocular cyclopentolate, including adverse reactions in susceptible patients |
| 33200390 | 2021 | Cohort | Int Ophthalmol | Compared effects of 1% cyclopentolate and 1% tropicamide on laser flare meter readings in uveitis patients |
| 37681397 | 2024 | Cohort | Acta Ophthalmol | Role of short-acting mydriatics in posterior synechia formation after phacovitrectomy |
| 12194069 | 2002 | Cohort | Eye (Lond) | Changes in intraocular pressure after diagnostic mydriasis with 1% cyclopentolate |
| 15506601 | 2004 | Cohort | Eur J Ophthalmol | Effects of cyclopentolate on intraocular pressure and retrobulbar haemodynamics in pseudoexfoliation syndrome and glaucoma |
| 17321460 | 2007 | Cohort | Optometry | Whether a single drop of 1% cyclopentolate gives adequate dilation in paediatric examinations |
| 2034449 | 1991 | Case report / Review | Ophthalmic Physiol Opt | Possible allergic reactions to cyclopentolate, with a literature review of uses and adverse reactions |
| 34928913 | 2021 | Case report | Psychiatr Danub | Cyclopentolate abuse comorbid with Behçet's disease (a safety signal, not efficacy) |
| 9885391 | 1999 | Case report | Ophthalmologica | Drug-induced transient myopia resolved after topical cyclopentolate |
Singapore Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN04201P | MINIMS CYCLOPENTOLATE HYDROCHLORIDE EYE DROPS 1% w/v | Solution | Not stated in the data compiled for this report |
The product is a valid single-ingredient licence held by Laboratoire Chauvin SA.
Safety Considerations
Package insert warnings, contraindications and drug interaction data are not available in the data compiled for this report (the interaction search returned no results). Please refer to the package insert for safety information.
The drug knowledge graph links cyclopentolate with the following conditions as contraindication relationships (derived from the knowledge graph, not from label text):
- Eye: angle-closure (closed-angle) glaucoma
- Cardiovascular: hypertension, heart disease, cardiovascular disease, coronary artery disease, sudden cardiac arrest, heart conduction disease, arteriosclerosis, atherosclerosis
- Endocrine and metabolic: diabetes mellitus, diabetic ketoacidosis, hyperthyroidism, Graves disease, thyrotoxicosis
- Urological: benign prostatic hyperplasia
- Neurological and genetic: brain injury, brain disease, Down syndrome
The literature also highlights allergic-type reactions, adverse effects in susceptible patients, and one case of cyclopentolate abuse. Systemic exposure carries a risk of central nervous system toxicity, which argues against non-ocular use of this ophthalmic formulation.
Conclusion and Next Steps
Decision: Hold
Rationale: The top-ranked predictions (cauda equina syndrome, neurogenic bladder, irritable bowel syndrome) rest on model scores alone and have no trials or literature. They are also not practical for a topical ophthalmic product with systemic safety concerns. The eye-related predictions (uveitis, iris disease, ciliary body disease) are mechanistically plausible but amount to symptomatic or diagnostic use backed by indirect evidence only. They are best treated as research questions, not repurposing candidates ready to advance.
To proceed, the following is needed:
- The Singapore package insert (warnings, contraindications, approved indication wording), downloaded from the HSA website
- Mechanism of action data from DrugBank
- For the eye-related candidates (uveitis first), a focused review or controlled study comparing cyclopentolate with established cycloplegics such as atropine or homatropine
- Confirmation that the route of administration is compatible with any non-ocular target, which is currently unassessed and unlikely for the ophthalmic formulation
- A clinical need assessment against current standard care, given that uveitis and panuveitis are treated mainly with corticosteroids and immunomodulators
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.