Triprolidine
| Evidence Level: L5 | Predicted Indications: 5 |
Table of Contents
Triprolidine: Nasal cavity disease
One-Sentence Summary
Triprolidine is a first-generation H1-receptor antagonist (antihistamine), originally used for allergic rhinitis, the common cold and other allergic conditions. but there are currently 0 clinical trials and only 2 loosely related publications supporting this direction. Urticaria also overlaps with an existing indication, so this is largely a duplicate of an approved use.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | Nasal cavity disease |
| TxGNN Prediction Score | 0.9983 |
| Evidence Level | L5 |
| Canada Market Status | Marketed (marketed DINs: 2 of 2) |
| Number of DINs | 2 (marketed: 2) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. Based on known pharmacology, triprolidine is a first-generation H1-receptor antagonist. Its efficacy in allergic rhinitis and related allergic conditions is established, and mechanistically it may be applicable to allergic urticaria.
Histamine released from mast cells is the central mediator of urticaria, so blocking H1 receptors is a reasonable approach. The prediction is therefore mostly a restatement of an existing use rather than true repurposing.
Other predicted indications are weaker. Cold urticaria is also histamine-mediated and plausible. Nasal cavity disease, pharyngitis and acute laryngopharyngitis likely reflect symptomatic relief of conditions close to existing indications. Recalcitrant atopic dermatitis and atopic IgE responsiveness have weak rationale, because pruritus in atopic dermatitis is largely non-histaminergic and triprolidine does not modulate IgE production.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
All are indirect evidence.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 2568212 | 1989 | Review | Clinical Pharmacy | Review of nonsedating H1 antagonists (terfenadine, astemizole, loratadine, acrivastine). Acrivastine is a metabolite-related derivative of triprolidine. No direct efficacy data for triprolidine in allergic urticaria. |
| 14283425 | 1965 | Experimental physiological study | British Journal of Dermatology | Triprolidine and skin response to ultraviolet radiation. No abstract available, and not controlled efficacy data for urticaria. |
| 2901993 | 1988 | RCT (indirect) | Dermatologica | Double-blind crossover trial in 18 patients with idiopathic cold urticaria. Acrivastine, a triprolidine derivative, and cyproheptadine both significantly reduced weal area versus placebo, with acrivastine more effective. Triprolidine itself was not tested. |
| 6377256 | 1984 | RCT | Pediatric Infectious Disease | Double-blind, placebo-controlled study in 142 children with purulent nasopharyngitis. It compared cephalexin alone or combined with pseudoephedrine/triprolidine, versus placebo. Results were not available in the data, and the relevance is tangential (pharyngitis prediction). |
Canada Market Information
| DIN | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 02169126 | TEVA-COTRIDIN | Not available | Not available |
| 02053403 | TEVA-COTRIDIN EXPECTORANT | Not available | Not available |
Safety Considerations
- Contraindication signals from the knowledge graph (not label text): hypertension, epilepsy, kidney disease, liver disease, pancreatitis, gallbladder disease, hypothyroidism, peptic ulcer disease, inflammatory bowel disease, diabetes mellitus and diabetic ketoacidosis, benign prostatic hyperplasia, coronary artery disease and myocardial infarction, ocular hypertension, atherosclerosis, heart conduction disease, sudden cardiac arrest, and others.
- Drug Interactions: The interaction screen returned 100 interactions, 20 of which were reviewed here.
- Major: potassium citrate and potassium chloride.
- Moderate: anticholinergics (atropine, hyoscyamine, scopolamine, glycopyrronium, dicyclomine, trospium, propantheline, clidinium, methscopolamine, mepenzolate), opioids and related agents (morphine, loperamide, eluxadoline), cannabinoids (dronabinol, nabilone), and metoclopramide. Additive anticholinergic or sedative effects are the likely concern.
Please also refer to the package insert for the full warnings and contraindications.
Conclusion and Next Steps
Decision: Hold
Rationale: The mechanism is plausible, but allergic urticaria overlaps with an existing indication, so this is not a genuinely new use. No triprolidine-specific clinical trials exist, and the available literature is indirect (mostly about the related compound acrivastine). Evidence is at L4, and the other predicted indications are L4–L5.
To proceed, the following is needed:
- Health Canada package insert warnings and contraindications (a blocking gap for safety screening), plus the approved indication text and dosage forms for both DINs
- Mechanism of action data (for example from DrugBank)
- Triprolidine-specific controlled efficacy data in urticaria (including cold urticaria)
- Confirmation of whether triprolidine was a studied component in the 1984 nasopharyngitis trial, and its results
- A clearer definition of whether the goal is a new use or confirmation of the existing labeled use
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.