Ozapim (Clozapine)

Clozapine is an atypical antipsychotic that acts on dopamine‑related pathways in schizophrenia and related disorders.

• Schizophrenia: Improves positive and negative symptoms in patients who have not responded to at least two other antipsychotics.
• Schizoaffective disorder: Reduces mood‑related symptoms and psychotic episodes when other treatments have failed.
• Reducing suicidal risk: Lowers the incidence of suicide in patients with schizophrenia or schizoaffective disorder who are at high risk.
• Parkinsonian psychosis: Helps manage psychotic symptoms in Parkinson’s disease when other options are unsuitable.
• Bipolar disorder (off‑label): May be used in resistant cases to control manic or depressive psychosis.

• Clozapine acts as a high‑affinity antagonist at dopamine D2 receptors while also blocking serotonin 5‑HT2A, muscarinic, histamine H1 and adrenergic receptors. This broad receptor profile modulates dopaminergic and serotonergic neurotransmission, reducing psychotic symptoms and stabilising mood in treatment‑resistant patients.

Clozapine may produce a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Sedation
• Weight gain
• Constipation
• Salivary hypersalivation
• Dizziness
• Tachycardia

Serious or Rare Side Effects

• Agranulocytosis
• Myocarditis
• Seizures
• Orthostatic hypotension
• Metabolic syndrome
• Pulmonary embolism

Clozapine requires careful monitoring and patient education before and during therapy.

• Blood monitoring: Perform regular full‑blood counts to detect agranulocytosis early.
• Cardiovascular assessment: Evaluate heart function and monitor blood pressure regularly.
• Metabolic screening: Check weight, glucose and lipid profiles at baseline and periodically.
• Seizure risk: Assess history of seizures; adjust dose if needed.
• Drug‑interaction vigilance: Review concomitant medications for additive CNS depression or hematologic effects.
• Store at ambient temperature: keep in original container, protect from moisture and direct sunlight.

Clozapine interacts with several medicines that can affect its safety or efficacy.

Major Interactions (Avoid)

• Ciprofloxacin: May increase clozapine plasma levels, raising toxicity risk.
• Fluvoxamine: Potently inhibits CYP2D6, leading to elevated clozapine concentrations.
• Smoking cessation: Loss of CYP1A2 induction can sharply increase drug levels.

Moderate Interactions (Monitor Closely)

• Benzodiazepines: May enhance sedation and respiratory depression.
• Antihypertensive agents: Can cause additive hypotensive effects.
• Anticholinergic drugs: May worsen constipation and urinary retention.