Minimum Gap Between Olanzapine 10mg Oral Doses
Olanzapine 10mg oral should be administered once daily, with dose adjustments occurring at intervals of not less than 1 week, as steady-state plasma concentrations are not achieved until approximately 1 week in typical patients. 1
Standard Dosing Interval
- Olanzapine is administered on a once-daily schedule without regard to meals 1
- The elimination half-life of olanzapine is approximately 37.2 hours in adolescents and similar in adults, supporting once-daily dosing 2
- Steady-state concentrations require approximately 1 week to achieve, which is why dose adjustments should not occur more frequently than weekly intervals 1
Context-Specific Dosing Intervals
For Chemotherapy-Induced Nausea and Vomiting (CINV)
- Olanzapine 10mg is given once daily for 4 consecutive days: one dose before highly emetogenic chemotherapy, then daily for 3 additional days 3, 4
- This represents a 24-hour interval between doses in the antiemetic regimen 3
For Acute Agitation (Intramuscular Route)
- When using IM olanzapine for acute agitation, doses can be repeated, though the FDA label and clinical trials used IM formulations with different pharmacokinetics than oral 5, 4
- For oral olanzapine in acute settings, accelerated titration studies used once-daily dosing (10mg daily, increased to 20mg daily as early as day 3) 6
Important Safety Considerations
- Do not increase oral doses more frequently than weekly intervals because steady-state has not been achieved 1
- Plasma olanzapine concentrations demonstrate dose-proportional increases, with Cmax occurring several hours after oral administration 7
- The 24-hour dosing interval is standard across all approved indications for oral olanzapine 1, 8
Clinical Pitfall to Avoid
- Avoid the temptation to dose more frequently than once daily for oral olanzapine, even in acute agitation scenarios, as the long half-life (approximately 37 hours) means drug accumulation will occur with more frequent dosing 2
- If inadequate response occurs within the first 24 hours, consider adding adjunctive lorazepam rather than redosing olanzapine 6