Olanzapine

=Olanzapine=

How it works
Olanzapine helps to correct chemical imbalances in the brain, which may cause mental illness. //Antipsychotic actions are thought to be mediated (at least in part) by blockade of dopaminergic transmission in various parts of the brain (in particular the limbic system). Current evidence suggests://
 * //all effective antipsychotics block D2 receptors//
 * //differential blockade of other dopamine receptors (eg D1) may influence therapeutic and adverse effects//
 * //antagonism of other receptors may influence antipsychotic activity, eg 5HT2 antagonism with some agents.//

Questions to Ask
- What medications? //anticholinergics, glucose-lowering agents (can increase glucose), carbamazepine (increased metabolism), ritonavir// //(increased metabolism)////, fluvoxamine// //(decreased metabolism)// - medical conditions? //Parkinson's disease (being a dopamine antagonist), epilepsy (may reduce seizure threshold), respiratory failure (causes CNS depression), risk of prolonged QT interval (increases arrhythmia risk), diabetes (can cause weight gain and raise BSLs)// - allergies?

How to take
//Olanzapine comes as either a wafer or a tablet and can be taken with or without food. Wafers should be handled carefully with dry hands as they may break up. They can be dissolved directly in the mouth or placed in a glass of water, juice, milk or coffee (not cola drinks).//

Schizophrenia //and related psychoses//, oral, start at 10 mg daily, increasing daily dose by 2.5–5 mg as clinically indicated, to 20 mg daily or more. //Agitation in schizophrenia or acute mania//, IM, 5–10 mg, followed if necessary by further doses of up to 10 mg at 2 and 6 hours after initial dose; maximum 30 mg in 24 hours. //Acute mania and maintenance treatment in bipolar disorder//, oral, 5–20 mg daily. //Oral//, start with 5 mg daily.
 * Adult:**
 * Elderly, renal or hepatic impairment:**

Side effects
- drowsiness, restlessness or difficulty sitting still, weight gain, dizziness, increased appetite, constipation, dry mouth, swelling of your hands, feet and ankles, unusual tiredness or weakness
 * Common:** hyperglycaemia (random blood glucose at upper limit of normal), type 2 diabetes, weight gain, peripheral oedema, constipation
 * Infrequent:** EPSE, elevation of liver transaminases
 * Rare:** rhabdomyolysis, VTE

Other advice?

 * response to tablets may occur in 1–2 weeks; allow 2–3 months for full trial
 * it is possible to overlap drugs when switching from another antipsychotic provided there is close supervision and monitoring
 * after stopping depot antipsychotic, start oral olanzapine at scheduled time of next injection
 * experts suggest that doses >20 mg daily (the current maximum suggested in manufacturer’s product information) may be required in some patients with schizophrenia
 * use wafer formulation for acutely psychotic patients, those who have difficulty swallowing tablets, or to help ensure compliance
 * check glucose tolerance if patient gains weight
 * tablets may be used in low doses for behavioural disturbance in the elderly; when used at the lower end of the dose range extrapyramidal reactions and hypotension are relatively uncommon
 * Tell your doctor if you start or stop smoking, as your dose may need to be changed.

CMI
[|Zyprexa] [|AMH]