Generic
Olanzapine
22 brands available in the market
At a glance
Olanzapine is an atypical antipsychotic used for schizophrenia and mania in bipolar disorder. It blocks dopamine and serotonin receptors to improve mood, thoughts and behavior.
Description
Olanzapine is an antipsychotic agent with affinities for serotonin 5HT2A/2C, 5HT3, 5HT6; dopamine D1, D2, D3, D4, D5; cholinergic muscarinic receptors M1-M5; α1 adrenergic; and histamine H1 receptors. Its mechanism of action is mediated through a combination of dopamine and serotonin type 2 (5HT2) antagonism.
Indications
- Schizophrenia and related psychoses (positive and negative symptoms)
- Acute manic or mixed episodes in bipolar disorder
Therapeutic class
Atypical Neuroleptic Drugs
Pharmacological class
Atypical Antipsychotic
Pharmacology
Olanzapine blocks dopamine D2 and serotonin 5HT2A receptors to help control mood, thoughts and behavior. It also has affinity for other receptors contributing to its side effect profile.
Mechanism of action
Controls schizophrenia and mania symptoms by blocking dopamine and serotonin receptors.
Dosage
Adult Dose (Oral):
- Schizophrenia: 5-10 mg/day (initial); increase by 5 mg/day weekly; maintenance: 10-20 mg/day; max 20 mg/day
- Mania (monotherapy): 10-15 mg/day (initial); 5-20 mg/day (maintenance)
- Mania (with lithium/valproate): 10 mg/day (initial); 5-20 mg/day (maintenance)
- Hepatic/Renal impairment: 5 mg/day (initial)
Pediatric Dose (13-17 years): 2.5-5 mg/day (initial); target 10 mg/day; range 2.5-20 mg/day
Administration
- Swallow tablet whole; do not chew, crush or break
- Take at the same time each day
- May be taken with or without food
- Gradual tapering for discontinuation
Missed dose
If you miss a dose, take it as soon as you remember; skip if it's almost time for next dose; do not double the dose.
Side effects
Common Side Effects:
- Somnolence
- Weight gain
- Increased appetite
- Elevated glucose and triglyceride levels
- Dizziness
- Akathisia
- Parkinsonism
- Dyskinesia
- Orthostatic hypotension
- Constipation and dry mouth
- Asthenia, edema, photosensitivity
Precautions & warnings
- Do not stop suddenly (may worsen symptoms)
- Caution in history of seizures
- Caution in low leukocyte/neutrophil counts
- Caution in hepatic impairment
- Caution while driving (may cause drowsiness and dizziness)
- Avoid alcohol
Contraindications
- Angle-closure glaucoma
- Lactation
- IM: History of CVS disease, heart surgery
Drug interactions
- May antagonize effects of levodopa and dopamine agonists
- CYP1A2 or glucuronyl transferase inducers (omeprazole, rifampicin) increase clearance
- Carbamazepine increases clearance
- Activated charcoal reduces bioavailability by 50-60%
- Caution with centrally acting drugs and alcohol
Food interactions
Alcohol may cause excessive drowsiness; avoid.
Use in pregnancy
Use in Pregnancy: Olanzapine may be unsafe during pregnancy; animal studies show evidence of fetal harm.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Olanzapine is probably unsafe during breastfeeding; may pass into breast milk and harm the baby.
Pediatric use
Not studied in children under 18 years; dose established for 13-17 years.
Geriatric use
Elderly (65 years+): Starting dose 5 mg/day.
Renal / hepatic impairment
Renal Impairment: Safe in kidney disease; no dose adjustment needed.
Hepatic Impairment: Caution in liver disease; starting dose 5 mg/day.
Overdose effects
Overdose: Somnolence, confusion, ataxia, tachycardia, hypotension, seizures; symptomatic treatment.
Storage conditions
Store below 30°C; protect from light & moisture; keep out of reach of children.
Chemical structure
Olanzapine