Lapozan (Olanzapine)

Olanzapine is an atypical antipsychotic used in the management of major psychotic and mood disorders.

• Schizophrenia: reduces psychotic symptoms such as delusions, hallucinations and thought disorder.
• Bipolar I disorder (manic or mixed episodes): controls acute mania and stabilises mood.
• Maintenance therapy for bipolar disorder: helps prevent recurrence of manic and depressive episodes.

• Olanzapine acts as an antagonist at dopamine D2 receptors and serotonin 5‑HT2A receptors, with additional activity at histamine H1, muscarinic and adrenergic receptors. This receptor profile modulates neurotransmission in brain pathways implicated in psychosis and mood regulation, leading to symptom improvement.

Olanzapine may cause a range of adverse reactions, from mild to severe.

Common Side Effects

• Weight gain: increased appetite and caloric intake.
• Sedation: drowsiness or fatigue.
• Dry mouth: reduced salivation.
• Constipation: slowed gastrointestinal motility.
• Dizziness: light‑headedness, especially when standing.
• Increased appetite: may contribute to weight changes.

Serious or Rare Side Effects

• Neuroleptic malignant syndrome: rare but life‑threatening reaction.
• Agranulocytosis: severe drop in white blood cells.
• Hyperglycemia: marked increase in blood sugar levels.
• Tardive dyskinesia: involuntary movements with long‑term use.
• Seizures: heightened risk in predisposed individuals.
• Myocarditis: inflammation of the heart muscle.

Before initiating olanzapine therapy, clinicians should consider several safety measures.

• Metabolic monitoring: regularly assess weight, glucose and lipid levels.
• Cardiovascular assessment: evaluate for existing heart disease or risk factors.
• Seizure risk: use cautiously in patients with a history of seizures.
• Elderly patients: avoid use in dementia‑related psychosis due to increased mortality.
• Discontinuation: taper gradually to minimise withdrawal or relapse.
• Store at room temperature: keep in original packaging, protect from moisture and direct sunlight.

Olanzapine can interact with other medicines, altering its effectiveness or safety.

Major Interactions (Avoid)

• Strong CYP1A2 inhibitors (e.g., fluvoxamine): may increase olanzapine levels.
• Other antipsychotics: additive central nervous system effects.
• CNS depressants (alcohol, benzodiazepines): heightened sedation and respiratory depression.

Moderate Interactions (Monitor Closely):\n- CYP1A2 inducers (e.g., smoking, carbamazepine): may reduce efficacy.

• Lithium: increased risk of neurotoxicity.
• QT‑prolonging agents: potential for cardiac rhythm disturbances.