Prilocaine
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Prilocaine: Papillary conjunctivitis
One-Sentence Summary
Prilocaine is an amide-type local anaesthetic, used topically in India. The TxGNN model predicts it may be effective for Neuralgia (the top-ranked prediction with real supporting evidence), with 2 clinical trials and 14 publications currently supporting this direction. The evidence is mostly small, dated studies of the lidocaine/prilocaine combination (EMLA), so the prilocaine-specific signal is weak.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Papillary conjunctivitis |
| TxGNN Prediction Score | 0.9978 |
| Evidence Level | L5 |
| India Market Status | Listed in a compiled Indian medicine price dataset (19 of 19) – CDSCO approval status is not included in this data |
| Number of Listed Products | 19 (valid: 19) |
| Recommended Decision | Hold (research question; see Conclusion) |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the compiled data. Based on known pharmacology, prilocaine is a sodium channel blocker local anaesthetic. It reduces nerve excitability and ectopic discharge in peripheral nociceptors.
The original indications (premature ejaculation and dyspareunia) are treated by topically reducing sensory input from the genital area. Neuralgia, particularly postherpetic neuralgia (PHN), is also driven by hyperexcitable peripheral sensory fibres. A topical sodium channel blocker is therefore mechanistically plausible for localised neuropathic pain.
Historical reports describe the lidocaine/prilocaine eutectic mixture (EMLA) in PHN, including pharmacokinetic data. However, the evidence is small and dated, and it uses a combination product, so the independent contribution of prilocaine is unclear.
Other predictions have much weaker support. Several (papillary conjunctivitis, manic bipolar disorder, bronchitis, migraine with brainstem aura and rosacea conjunctivitis) rest on model prediction alone with no trials or literature. Literature for atopic eczema and allergic asthma mainly signals safety risk rather than benefit.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT00916942 | Phase 2 | Completed | 20 | Open-label study of lidocaine 2.5%/prilocaine 2.5% cream as pre-treatment before the capsaicin 8% patch (NGX-4010) in postherpetic neuralgia; evaluated tolerability, not efficacy against neuralgia |
| NCT06899438 | N/A | Completed | 38 | Botulinum toxin type A vs prilocaine injection in myofascial pain syndrome; relevance to prilocaine is indirect |
Evidence for migraine disorder (rank 4) is also thin. One N/A-phase topical analgesic study (NCT02403687, 300 participants) has an unverified link to migraine and prilocaine.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 2493878 | 1989 | Clinical study | BMJ | Lignocaine-prilocaine cream in postherpetic neuralgia |
| 2616182 | 1989 | Clinical study | Pain | EMLA 5% cream applied for 24 h in 12 patients with refractory PHN; pain scores improved significantly at 6 h, with pharmacokinetic profile |
| 1430539 | 1992 | Review | J Dermatol Surg Oncol | EMLA review; lists postherpetic neuralgia among other indications |
| 22182397 | 2011 | Clinical study | BMC Anesthesiology | Tolerability of the capsaicin 8% patch after lidocaine/prilocaine pretreatment in PHN |
| 8695081 | 1996 | Case report | J Clin Anesth | Successful EMLA treatment of PHN resistant to other therapies |
| 10342425 | 1999 | Experimental | Pain | EMLA pre-treatment failed to reduce pain from 1% topical capsaicin in 9 healthy subjects |
| 41777672 | 2026 | Retrospective cohort | Front Aging Neurosci | EMLA alone vs paravertebral block plus EMLA for capsaicin patch tolerability in thoracic PHN |
| 23314014 | 2013 | Review | Curr Opin Support Palliat Care | Evidence-based approach to persistent wound-related pain |
| 7897165 | 1995 | Report | J Allergy Clin Immunol | EMLA-induced allergic contact dermatitis; prilocaine as an immunogen |
| 40519459 | 2025 | Review | Cureus | Topical anaesthetics have higher systemic absorption and toxicity risk in barrier-compromised skin |
India Market Information
All 19 registrations are valid products, mainly topical creams, gels and an ointment. No approved indication text is recorded for any of them. A selection of the main authorisations:
Review correction (2026-11-06): Originally stated: “All 19 registrations are valid single-ingredient products, mainly topical creams, gels and an ointment.” Removed: it described the products as single-ingredient or combination products in a way that did not match the Indian medicine data (the Indian Medicine Dataset as of 2026-11-06). Source: Indian Medicine Dataset.
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 174279 | Prilox Cream (Neon Laboratories) | Cream, 5 g tube | Not recorded |
| 245124 | Xynova P Cream (Troikaa) | Cream, 5 g tube | Not recorded |
| 244144 | Xynova P Gel (Troikaa) | Gel, 30 g tube | Not recorded |
| 58540 | Dolocaine Cream (Cadila) | Cream, 5 g tube | Not recorded |
| 73043 | Emlap Gel (Dr Reddy’s) | Gel, 30 g tube | Not recorded |
Safety Considerations
- Contraindications flagged in the knowledge graph (not label text): hypertension, epilepsy, kidney disease, liver disease, diabetes mellitus, coronary artery disease and myocardial infarction, heart conduction disease and atrioventricular block, respiratory failure, angle-closure glaucoma, myasthenia gravis and other neuromuscular junction disease, butyrylcholinesterase deficiency, hemoglobinopathy, and hyperthyroidism.
- Drug interactions: 22 interactions were identified, most rated Major. Many involve agents that can cause methemoglobinemia, including:
- Dapsone (oral and topical)
- Primaquine, chloroquine, quinine and tafenoquine
- Nitrites and nitric oxide (amyl nitrite, nitrous acid)
- Rasburicase
- Sulfasalazine
- Silver nitrate and silver sulfadiazine
- Other local anaesthetics (lidocaine, topical benzocaine, topical cinchocaine)
- Metoclopramide
Moderate (liposomal morphine) and Minor (hyaluronidase) interactions were also reported.
- Literature safety signals: methemoglobinemia and seizures after EMLA use in a young child with atopic dermatitis, higher systemic absorption through compromised skin, contact allergy, and purpura.
Package insert warnings were not available in the compiled data, so refer to the package insert for full safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The prilocaine-specific evidence is limited to small, dated studies of the lidocaine/prilocaine combination (EMLA). It is supported by a plausible sodium-channel mechanism for neuralgia, but it does not isolate prilocaine’s contribution. All other predictions rest on model scores alone or on safety-oriented literature. Neuralgia is worth pursuing as a research question rather than a go decision.
To proceed, the following is needed:
- Package insert warnings and contraindications from the India regulatory source (currently a blocking gap for safety screening)
- Mechanism of action data from DrugBank
- Controlled studies of topical lidocaine/prilocaine in neuralgia that include a comparator and clearly separate the effect of prilocaine
- A safety plan for methemoglobinemia risk, covering the interacting drugs, barrier-compromised skin, and young or vulnerable patients
- Confirmation of route and formulation compatibility with the intended neuropathic pain use
Review Log
Below is the review log for this page: statements checked against official Indian medicine data (the Indian Medicine Dataset used by this site). Corrections are limited to basic factual statements; model predictions, evidence levels, and conclusions were not rewritten.
| Review date | Item | Action | Source |
|---|---|---|---|
| 2026-11-06 | Removed: “single-ingredient” | Corrected | Indian Medicine Dataset |
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.