Zuclopenthixol is indicated for the management of the manifestations of schizophrenia. It is used for the initial treatment of acute psychotic episodes or exacerbations of psychosis associated with schizophrenia.

Zuclopenthixol is a thioxanthene derivative with high affinity for dopamine D1 and D2 receptors. It also has high affinity for α1-adrenergic and 5-HT2 receptors. It shows weaker antihistaminic (H1 receptor blocking) activity and even lower affinity for muscarinic cholinergic and α2-adrenergic receptors.

Zuclopenthixol Tablets: When initiating treatment with Zuclopenthixol tablets, it is recommended that the drug be given in divided doses (BID or TID). During the maintenance phase of treatment, Zuclopenthixol tablets may be given as a single nighttime dose. For acute psychosis, the usual starting dose is 10–50 mg/day, which may be increased by 10–20 mg every 2–3 days, according to the patient’s response. The usual therapeutic range is 20 mg to 60 mg daily. However, as with other antipsychotic drugs, some patients may require lower, while others may require higher dosage in order to obtain optimal benefit. Daily dosage higher than 100 mg is not recommended. For maintenance therapy, dosage should be reduced to the lowest level compatible with symptom control. The usual maintenance dose is 20–40 mg/day.

Zuclopenthixol Acuphase: Dosage should be individually adjusted according to the patient’s condition. The usual dose is 50–150 mg (1–3 ml) administered intramuscularly and repeated if necessary, at intervals of 2–3 days. Some patients may need an additional injection 1 or 2 days after the first injection.

Zuclopenthixol Depot: Close supervision is required during the period following initiation of Zuclopenthixol Depot treatment, in order to minimize the risk of over-medication or insufficient suppression of psychotic symptoms. Supplemental oral antipsychotic medication may be required in diminishing dosage during this period. The usual maintenance dose is 150–300 mg intramuscularly every 2–4 weeks. Some patients may require higher or lower doses, or shorter intervals between doses.

Drugs that may interact with Zuclopenthixol include:

• Tricyclic antidepressants
• Guanethidine and similar antihypertensive medicines
• Barbiturates and similar sedative medicines
• Levodopa and similar drugs (used in Parkinson’s disease)
• Metoclopramide (used for gastrointestinal disorders)
• Other antipsychotic medicines (e.g. thioridazine)
• Medicines affecting heart rhythm (e.g. quinidine, amiodarone, sotalol, erythromycin, moxifloxacin, lithium)

Acute alcohol, barbiturate, or opiate intoxication.

• CNS depression of any cause, comatose states, suspected or established subcortical brain damage, or circulatory collapse.
• Hypersensitivity to thioxanthenes, zuclopenthixol, or any component of the formulation.

Common side effects include tachycardia, palpitations, tremor, dystonia (twisting or repetitive movements or abnormal posture due to sustained muscle contractions), and hypertonia (increased muscle stiffness).

The safety of Zuclopenthixol during pregnancy has not been established. It is excreted in human milk, and its safety during breastfeeding is also not established.

Use with caution if:

• You have used Zuclopenthixol or other antipsychotics before and had problems
• You are taking any other prescription or non-prescription medicines
• You are pregnant, planning pregnancy, or breastfeeding
• You consume alcohol regularly
• You have liver disease, Parkinson’s disease, or a history of seizures
• You have dementia or glaucoma
• You have kidney problems
• You have stroke risk factors (smoking, hypertension)
• You have low potassium or magnesium levels
• You have cardiovascular disease history
• You or your family have a history of blood clots
• You are receiving cancer treatment (Zuclopenthixol depot only)
• You are using other antipsychotic medicines

Safety and efficacy in children under 18 years have not been established; therefore, use is not recommended.

Overdose symptoms may include somnolence, coma, abnormal movements, convulsions, shock, and abnormal body temperature (high or low).

Phenothiazine related drugs

Store between 15°C and 25°C. Protect from light.