What is the maximum dose of Olanzapine (olanzapine) that can be administered within 2 hours of an initial 10mg dose?

Olanzapine Dosing After Initial 10mg Dose

After an initial 10mg dose of intramuscular olanzapine, an additional 10mg may be administered 2 hours later, but the total daily dose should not exceed 30mg and injections should not be given more frequently than 2 hours apart. 1

Maximum Dosing Parameters for Acute Agitation

The FDA-approved dosing algorithm for intramuscular olanzapine specifies:

• Maximum single dose: 10mg 1
• Minimum interval between doses: 2 hours after the initial dose, then 4 hours after the second dose 1
• Maximum total daily dose: 30mg (e.g., three 10mg injections given 2-4 hours apart) 1

Given that 10mg has already been administered, you can give up to 10mg more at the 2-hour mark 1

Critical Safety Considerations

Maximal dosing of intramuscular olanzapine (3 doses of 10mg administered 2-4 hours apart) is associated with substantial occurrence of significant orthostatic hypotension 1

• Assess for orthostatic hypotension before administering any subsequent doses 1
• Do not administer additional doses to patients with clinically significant postural changes in systolic blood pressure 1
• The safety of doses >30mg daily or injections given more frequently than the specified intervals has not been evaluated in clinical trials 1

Alternative Dosing Options

Lower doses of 5mg or 7.5mg may be considered when clinical factors warrant, particularly in patients who may be more sensitive to the medication 1

Consider transitioning to oral olanzapine (5-20mg/day) as soon as clinically appropriate if ongoing therapy is indicated 1

Evidence Supporting Efficacy

Clinical trials demonstrated that olanzapine IM in doses ranging from 2.5-10mg was effective for acute agitation, with the 10mg dose showing superior efficacy to placebo by 2 hours 2

Comparative studies showed olanzapine 10mg IM was equivalent to haloperidol 7.5mg IM for acute agitation, with fewer extrapyramidal side effects 3, 4

Common Pitfalls to Avoid

• Do not combine olanzapine IM with diazepam, lorazepam for reconstitution, or haloperidol in the same syringe due to precipitation or degradation 1
• Do not administer intravenously or subcutaneously - intramuscular route only 1
• The efficacy of repeated doses for agitated patients has not been systematically evaluated in controlled trials, so clinical judgment is essential 1