Overview
Zuclopenthixol is a typical antipsychotic medication of the thioxanthene class, primarily used for the treatment of schizophrenia and other psychotic disorders. It acts as a dopamine D1/D2 receptor antagonist with additional effects on serotonin, histamine, and adrenergic receptors. Available in oral and depot injection formulations, it provides long-term management of psychotic symptoms.
Mechanism of Action
Zuclopenthixol acts primarily as a dopamine D1 and D2 receptor antagonist in the central nervous system, with additional antagonistic effects on serotonin (5-HT2A), histamine (H1), and alpha-1 adrenergic receptors. This multi-receptor blockade contributes to its antipsychotic effects and side effect profile.
Indications
- Schizophrenia
- Acute psychotic episodes
- Maintenance therapy for chronic psychotic disorders
- Mania and hypomania in bipolar disorder
- Severe agitation and aggression in psychotic patients
Dosage
Oral: Initial dose 20-30 mg daily in divided doses, maintenance 20-50 mg daily. Depot injection: Clopixol Acuphase (acute treatment) 50-150 mg IM, repeated after 2-3 days if needed. Clopixol Depot (maintenance) 200-400 mg IM every 2-4 weeks. Dosage must be individualized based on patient response and tolerability.
Contraindications
- Hypersensitivity to zuclopenthixol or thioxanthenes
- Comatose states
- CNS depression from alcohol, barbiturates, or opioids
- Severe cardiovascular disease
- Parkinson's disease
- Pheochromocytoma
- Severe liver impairment
- Narrow-angle glaucoma
Side Effects
- Extrapyramidal symptoms (dystonia, akathisia, parkinsonism)
- Sedation and drowsiness
- Orthostatic hypotension
- Anticholinergic effects (dry mouth, constipation, blurred vision)
- Weight gain
- Hyperprolactinemia (galactorrhea, menstrual irregularities)
- QT prolongation
- Tardive dyskinesia
- Neuroleptic malignant syndrome
- Hepatic enzyme elevation
- Photosensitivity
- Sexual dysfunction
Interactions
- CNS depressants (alcohol, benzodiazepines, opioids): enhanced sedation
- Anticholinergic drugs: increased anticholinergic effects
- Antihypertensives: potentiated hypotension
- QT-prolonging drugs (antiarrhythmics, certain antibiotics): increased arrhythmia risk
- Dopamine agonists: reduced efficacy
- Enzyme inducers (carbamazepine, phenytoin): reduced zuclopenthixol levels
- Enzyme inhibitors (fluoxetine, paroxetine): increased zuclopenthixol levels