Pimozide
| Evidence Level: L3 | Predicted Indications: 10 |
Table of Contents
Pimozide: From Tourette Syndrome to Trichotillomania
One-Sentence Summary
Pimozide is a dopamine D2 antagonist antipsychotic, originally used to treat Tourette syndrome. The TxGNN model predicts it may be effective for trichotillomania (compulsive hair pulling). Support is limited: no registered clinical trials and 9 publications, mostly reviews, plus one small, dated augmentation study from 1992.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Tourette syndrome |
| Predicted New Indication | Trichotillomania |
| TxGNN Prediction Score | 1.0000 |
| Evidence Level | L3 |
| India Market Status | Listed in a compiled Indian medicine price dataset (at least 20) – CDSCO approval status is not included in this data |
| Number of Listed Products | at least 20 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in the data compiled for this report. Pimozide is known to be a dopamine D2 receptor antagonist, and its efficacy in Tourette syndrome is established.
Trichotillomania and Tourette syndrome share features of repetitive, habit-like behaviour. Both are thought to involve dopaminergic dysregulation in cortico-striatal-thalamic circuits. A 1992 study (PMID 1532960) reported that low-dose pimozide added to serotonin reuptake inhibitors was helpful in trichotillomania. A dermatology review (PMID 15554735) also covers pimozide use in related psychodermatologic conditions.
However, the evidence is small-scale and dated. More recent evidence maps favour other approaches, such as SSRIs, N-acetylcysteine, olanzapine and behavioural therapy.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 15554735 | 2004 | Review | Am J Clin Dermatol | Comprehensive review of pimozide in dermatologic practice, including monosymptomatic hypochondriacal psychosis |
| 36802832 | 2023 | Evidence mapping / Review | J Cutan Med Surg | Maps RCT evidence for pharmacological treatment of primary psychodermatologic disorders |
| 30446201 | 2018 | Review | Clin Dermatol | Antipsychotic drugs in dermatology, acting through central and peripheral receptor effects |
| 1532960 | 1992 | Clinical study (small augmentation study) | J Clin Psychiatry | Low-dose pimozide augmentation of serotonin reuptake blockers in trichotillomania |
| 27320510 | 2016 | Review | Tijdschr Psychiatr | Treatment options for paediatric trichotillomania |
| 10497682 | 1999 | Review | Ann Acad Med Singap | Overview of trichotillomania as an under-diagnosed psychiatric condition |
| 11475941 | 2001 | Review | CNS Drugs | Psychogenic excoriation: clinical features and treatment approaches |
| 10357517 | 1999 | Case series | J Child Adolesc Psychopharmacol | Risperidone (not pimozide) added in SRI-resistant trichotillomania; notes earlier benefit of pimozide |
| 10900563 | 2000 | Review | Int J Psychiatry Med | Delusional parasitosis clinical profile (indirect relevance) |
India Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 182021 | Pimolite 4mg Tablet | Strip of 10 tablets | Not stated |
| 165606 | Orap 4mg Tablet | Strip of 10 tablets | Not stated |
| 134766 | Mozep 2 Tablet | Strip of 10 tablets | Not stated |
| 176959 | Pimide 2mg Tablet | Strip of 10 tablets | Not stated |
| 163388 | Orap 2mg Tablet | Strip of 10 tablets | Not stated |
All 20 licences are valid single-ingredient oral tablets. The five above are a selection.
Safety Considerations
- Contraindications (model-derived associations from the TxGNN model (deep learning), not label text; these may reflect similarities the model learned between related diseases, not biological evidence): long QT syndrome (including familial), torsades de pointes, sudden cardiac arrest, heart conduction disease, epilepsy, kidney disease, liver disease, gallbladder disease, potassium deficiency, benign prostatic hyperplasia, glaucoma, neuroleptic malignant syndrome, neutropenia, agranulocytosis, leukopenia and related congenital neutropenias, female breast carcinoma, and Alzheimer disease.
- Drug Interactions: 247 interactions were recorded. Major ones include hydrocortisone, amphotericin B (including the lipid complex), bupropion, aprepitant, morphine, lorcaserin, cimetidine, potassium citrate, clarithromycin, picosulfuric acid, and polyethylene glycol with electrolytes. Moderate ones include famotidine, epinephrine, hyoscyamine, loperamide, atropine, bisacodyl, glycopyrronium, and dicyclomine.
Please also refer to the package insert for label-based warnings and contraindications, which were not available for this report.
Conclusion and Next Steps
Decision: Hold
Rationale: Support for trichotillomania is limited to a small 1992 augmentation study and reviews, with no registered trials. Pimozide also carries QT-prolongation risk and a heavy interaction burden, while better-supported alternatives exist.
To proceed, the following is needed:
- Package insert warnings and contraindications for the Indian-marketed products, which are required before safety screening
- Detailed mechanism of action data
- Modern controlled trial data for pimozide in trichotillomania, with a comparison against current options (SSRIs, N-acetylcysteine, olanzapine, behavioural therapy)
- A cardiac (QT/ECG) monitoring and drug interaction management plan
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.