What is the typical dosing for Zyprexa (olanzapine)?

Zyprexa (Olanzapine) Dosing Guidelines

For adults with schizophrenia or bipolar disorder, start with 5-10 mg orally once daily, with a typical target dose of 10-20 mg/day and a maximum of 20 mg/day. 1

Adult Dosing by Indication

Schizophrenia

• Starting dose: 5-10 mg orally once daily 1
• Target range: 10-20 mg/day 2
• Dose adjustments should occur at intervals of not less than 24 hours 1
• When adjustments are needed, use increments/decrements of 5 mg 1
• Maximum dose: 20 mg/day (doses above this have not been evaluated in clinical trials for safety) 1

Bipolar I Disorder (Manic or Mixed Episodes)

• Monotherapy: Begin with 10 or 15 mg once daily 1
• Adjunctive therapy (with lithium or valproate): Begin with 10 mg once daily 1
• Effective dose range: 5-20 mg/day 1
• Maximum dose: 20 mg/day 1

Acute Agitation (Intramuscular)

• Recommended dose: 10 mg IM 1
• Lower doses of 5 or 7.5 mg IM may be considered when clinical factors warrant 3, 1
• Alternative doses of 2.5 mg, 5 mg, or 7.5 mg IM can be used based on clinical factors 3
• If additional doses are needed, subsequent doses up to 10 mg may be given 1
• Do not exceed 30 mg total daily dose 1
• Minimum interval between doses: 2 hours after initial dose, 4 hours after second dose 1

Adolescent Dosing (Ages 13-17)

Schizophrenia and Bipolar I Disorder

• Starting dose: 2.5 or 5 mg once daily 1
• Target dose: 10 mg/day 1
• Effective dose range: 2.5-20 mg/day 1
• When adjustments are needed, use increments/decrements of 2.5 or 5 mg 1
• Maximum dose: 20 mg/day 1

Special Population Dosing

Elderly Patients

• Starting dose: 2.5-5 mg once daily 3, 2
• Maximum recommended dose: 5-10 mg/day (most elderly patients respond adequately to doses in this range) 3
• Avoid doses above 10 mg/day as the risk-benefit ratio becomes unfavorable 3
• For patients with Alzheimer's disease or dementia: start with 2.5 mg once daily at bedtime, with a maximum of 10 mg/day (usually divided twice daily) 2

Elderly Patients Receiving IM Olanzapine

• Recommended dose: 5 mg IM 1
• Consider 2.5 mg IM for debilitated patients or those predisposed to hypotensive reactions 1

Hepatic Impairment

• Starting dose: 2.5 mg once daily 3

Administration Guidelines

Oral Administration

• Can be taken without regard to meals 1
• Available as standard tablets and orally disintegrating tablets (ZYDIS) 3, 1
• For ZYDIS: place entire tablet in mouth using dry hands; disintegrates rapidly and can be swallowed with or without liquid 1

Intramuscular Administration

• For intramuscular use only—do not administer IV or subcutaneously 1
• Inject slowly, deep into muscle mass 1
• Reconstitute with 2.1 mL Sterile Water for Injection to provide approximately 5 mg/mL 1
• Use immediately (within 1 hour) after reconstitution 1

Critical Safety Considerations

Monitoring Requirements

• Assess for orthostatic hypotension prior to subsequent IM doses, especially with maximal dosing (e.g., 3 doses of 10 mg administered 2-4 hours apart) 1
• Monitor for sedation and drowsiness, particularly in elderly patients 3
• Monitor for metabolic effects (weight gain, glucose abnormalities) with long-term use 3, 2
• Weight gain occurs in approximately 40% of patients, especially with high starting doses 4

Drug Interactions

• Use extreme caution when combining with benzodiazepines due to risk of oversedation and respiratory depression 3
• Fatalities have been reported with concurrent use of benzodiazepines and high-dose olanzapine 3
• Exercise caution when combining with metoclopramide, phenothiazines, or haloperidol to avoid excessive dopamine blockade 3

Black Box Warning

• Increased mortality in elderly patients with dementia-related psychosis 3

Maintenance Treatment

• For schizophrenia: maintain at 10-20 mg/day after achieving response 1
• For bipolar disorder: maintain at 5-20 mg/day after achieving responder status 1
• Continue at the lowest dose needed to maintain remission 1
• Periodically reassess the need for continued treatment 1

High-Dose Considerations

While the FDA-approved maximum is 20 mg/day, clinical practice data shows increasing use of higher doses 5. However, doses above 20 mg/day increase the risk of weight gain and elevated prolactin without established additional benefit for most patients 5. Higher doses may only be considered for selected patients with severe, treatment-resistant symptoms under enhanced monitoring 3, 5.