Prochlorperazine

Evidence Level: L5

Predicted Indications: 10

Prochlorperazine

Pharmacist Assessment Report

Prochlorperazine: From Schizophrenia to Retinal Dystrophy With or Without Extraocular Anomalies (Computational Prediction Only)

One-Sentence Summary

Prochlorperazine is a phenothiazine antipsychotic, originally used for schizophrenia. The TxGNN model’s top-ranked prediction is retinal dystrophy with or without extraocular anomalies, but no clinical trials and no publications support it, so it rests on model output alone. The best-supported direction among the predictions is manic bipolar affective disorder, which has 7 publications (mostly old case reports, reviews and safety reports) and no clinical trials.

Quick Overview

Item	Content
Original Indication	Schizophrenia (the Canadian licence records contain no approved indication text)
Predicted New Indication	Retinal dystrophy with or without extraocular anomalies
TxGNN Prediction Score	1.0000
Evidence Level	L5
Canada Market Status	Marketed (marketed DINs: 3 of 3)
Number of DINs	3 (marketed: 3)
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data is not available in the compiled data. Based on general pharmacology, prochlorperazine is a phenothiazine that blocks dopamine D2 receptors. This is consistent with its use in schizophrenia.

For the top prediction, retinal dystrophy, no mechanistic link is established. The score is very high, but it is a purely computational output. D2 antagonism has no known relevance to inherited retinal degeneration. Phenothiazines also carry ocular adverse effects, so the risk-benefit is unfavourable without supporting evidence.

The other top-ranked predictions are similarly unsupported. These include hydranencephaly, a congenital disorder of glycosylation, X-linked and syndromic myopia, Charcot-Marie-Tooth disease type 1G, polymicrogyria and atypical glycine encephalopathy. Most are congenital or monogenic conditions that a D2 antagonist is not expected to change.

The one biologically plausible prediction is manic bipolar affective disorder (score 0.9998). It is close to the original psychiatric use, and antipsychotics of this class are used for mania and acute agitation. Even so, its support is limited to old case reports, surveys and safety papers. Modern guideline-endorsed agents are available.

Clinical Trial Evidence

Currently no related clinical trials registered, for the top prediction or for manic bipolar affective disorder.

Literature Evidence

No literature is available for the top prediction (retinal dystrophy). The table below covers the best-supported prediction, manic bipolar affective disorder.

PMID	Year	Type	Journal	Key Findings
19461391	2009	Review	Journal of Psychiatric Practice	Use and safety of antipsychotic drugs during pregnancy, in the context of schizophrenia and related illness
26819726	2015	Cohort	Journal of Pharmaceutical Health Care and Sciences	Analysis of spontaneous adverse event reports on hyperglycaemia with antipsychotics
13617778	1959	Case report	Annales Médico-Psychologiques	Confusional dream-like attack caused by prochlorperazine in a mildly manic-depressive patient
14242542	1965	Review	Obstetrics and Gynecology	Approach to severe psychological disorders of the puerperium
14233737	1964	Review	American Journal of Psychiatry	Survey of electroshock therapy combined with phenothiazines and reserpine
14062306	1963	Review	La Tunisie Médicale	Emergency management of agitation in general practice
14222730	1964	Review	L’Encéphale	Psychodysleptic manifestations during treatment with psycholeptics

Canada Market Information

DIN	Product Name	Dosage Form	Approved Indication
00886432	PROCHLORAZINE	Not specified	Not specified
00789720	ODAN-PROCHLORPERAZINE	Not specified	Not specified
00886440	PROCHLORAZINE	Not specified	Not specified

Safety Considerations

Contraindications flagged in the knowledge graph (these come from knowledge-graph drug-disease edges, not from package insert text):

Cardiovascular: hypertension, orthostatic hypotension, postural orthostatic tachycardia syndrome, multiple system atrophy, long QT syndrome (including familial), torsades de pointes, coronary artery disease, myocardial infarction, coronary thrombosis
Neurological: epilepsy, basal ganglia disease, focal hand dystonia, blepharospasm
Haematological: thrombocytopenia, neutropenia, agranulocytosis
Hepatic, renal and gastrointestinal: liver disease, gallbladder disease, kidney disease, pyoureter, gastric ulcer
Metabolic and other: hyperglycaemia, obesity disorders (including monogenic obesity), benign prostatic hyperplasia, substance abuse/dependence, female breast carcinoma

Drug Interactions: 100 interactions were recorded. The 20 listed in the compiled data are mostly Moderate.

Major: bupropion, potassium citrate
Moderate (examples): metformin, pioglitazone, alogliptin, acarbose, chlorpropamide and canagliflozin (antidiabetics, with glycaemic effects); atropine, hyoscyamine and glycopyrronium (anticholinergics); morphine; epinephrine; clarithromycin; famotidine

Please refer to the package insert for label warnings and contraindications, which are not available in the compiled data.

Conclusion and Next Steps

Decision: Hold

Rationale: The top prediction, retinal dystrophy, is a purely computational result with no trials, no literature and no mechanistic basis. All ranked predictions are L5, except manic bipolar affective disorder at L4, and that one is supported only by old reports and safety papers. Prochlorperazine also carries a substantial safety burden, including cardiac, neurological and ocular risks.

To proceed, the following is needed:

Health Canada package insert warnings and contraindications (a blocking gap for safety screening)
Mechanism of action data
For manic bipolar affective disorder, a structured review of the evidence against current guideline-endorsed agents, and a decision on whether it is worth pursuing as a research question
For the retinal and congenital predictions, preclinical support for a mechanism before any further evaluation
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.