Dose
Taken orally, 5-20mg per day, starting at 5mg/day and then increased slowly by increments of 5mg per day, giving a week between changes to allow levels to stabilize. Zyprexa brand olanzapine comes in 2.5mg, 5mg, 7.5mg, 10mg, 15mg, and 20mg tablets. The Zyprexa Zydis tablets are an orally disintigrating version for people who have a tendency to spit out their medication.

Law
Olanzapine is an unscheduled pharmaceutical available by prescription.

General
The peak plasma concetrations of olanzapine are achieved 6 hours after ingestion. The initial effects of olanzapine are sedation and, possibly, a dry mouth. The antipsychotic effect of olanzapine is not immediately apparent after single dosing. This is likely due to the fact that olanzapine accumulates over the period of a week to a steady state level in the bloodstream. These levels are roughly twice what would occur after a single dose of olanzapine.

Experimentally, olanzapine causes sedation in a a higher percentage of people than quetiapine or clozapine, however it is generally considered less sedating than either of these drugs. This makes olanzapine a very attractive choice for many patients who are bound to antipsychotics.

There is reason to believe that the 5-HT2 antagonism of olanzapine may have an antidepressant effect.

SideEffects
Mental side effects include agitation, akathisia, amnesia, anxiety, dizziness, euphoria, headache, hostility, insomnia, sleepiness, stuttering, akithisia (restlessness of the legs).

Physical side effects include chest pain, edema, hypotension, tachycardia, abdominal pain, constipation, dry mouth, increased appetite, PMS (in women), weight gain, joint pain, rash, fever, and occasional sexual side effects.

Interactions

• Carbamazepine reduces the effectiveness of olanzapine.
• Levodopa's effects may be blocked by the systemic antagonism of olanzapine.