Treatment With Depot Olanzapine

Abstract

Back to table of contents Previous article Next article Letter to the EditorFull AccessTreatment With Depot OlanzapineJohn Davis, M.D.John DavisSearch for more papers by this author, M.D.Published Online:1 Jul 2010https://doi.org/10.1176/appi.ajp.2010.10030396AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail To the Editor: I wish to expand on two points made in my editorial (1), published in the February 2010 issue of the Journal, and correct an error. An accidental injection of depot olanzapine into or near a vein can result from much of the dose being administered as one bolus, producing an overdose, which is manifested as confusion, disorientation, deliria, somnolence, dysarthria, ataxia, and coma or seizure (2). This occurs in approximately 0.07% (the correct value) of individuals per injection, or approximately 1% of patients each year, which cumulates year by year. Hopefully, clinicians will be meticulous about injection techniques, reducing the incidence. Eighty percent of the time, this syndrome starts within 1 hour after injection, 17% of the time within 1–3 hours, and 3% of the time after 3 hours, with the median time to incapacitation being 60 minutes (range: 10–300 minutes). There was no relationship of dose to seriousness of this adverse reaction. In addition, there were no fatalities. Patients completely recovered in a few days, and most agreed to go back on depot medication It is important to prevent the consequences of adverse effects (e.g., auto accidents) by observing the patient for 3 hours after the injection; having the patient leave the clinic with a responsible caregiver; being attentive to the nonspecific prodrome (feeling weak, dizzy, or generally bad); and avoiding sedative medications as well as epinephrine, dopamine, and other beta agonists because they may possibly worsen hypotension as a result of olanzapine's apha-1 properties.I do not think there is sufficient evidence to recommend tapering or not tapering oral drug doses or using a loading or intramuscular booster dose when switching to depot olanzapine, based on the following evidence. It takes 3–5 injections to reach steady state. Plasma levels decrease after the first injection, to as low as 5%–20% of the levels observed with oral drug formulation, but the half-life of D2 receptor blockade for oral and depot formulations is at least three times as long as that for plasma (3). Kane et al. (4) found the rate of relapse to be approximately 50% greater (not statistically significant) in the first few dosage intervals than the rate observed at steady state. The 405 mg per month dose was almost as effective as the dose of 300 mg every 2 weeks, indicating that monthly injection intervals can be of use. The dosage of 150 mg every 2 weeks is too low for many patients, and may possibly double the number of relapses when the observed difference is projected over years.Chicago, Ill.The author reports no financial relationships with commercial interests.References1 Davis JM : The use of depot medications in the treatment of schizophrenia. Am J Psychiatry 2010; 167:125–126 Link, Google Scholar2 Eli Lilly: Psychopharmacologic Drugs Advisory Committee Briefing Document: Zyprexa Olanzapine Pamoate (OP) Depot (Olanzapine Long-Acting Injection) Schizophrenia. Indianapolis, Ind, Eli Lilly, 2008 Google Scholar3 Mamo D , Kapur S , Keshavan M , Laruelle M , Taylor CC , Kothare PA , Barsoum P , McDonnell D : D2 receptor occupancy of olanzapine pamoate depot using positron emission tomography: an open-label study in patients with schizophrenia. Neuropsychopharmacology 2008; 33:298–304 Crossref, Medline, Google Scholar4 Kane JM , Detke HC , Naber D , Sethuraman G , Lin DY , Bergstrom RF , McDonnell D : Olanzapine long-acting injection: a 24-week, randomized, double-blind trial of maintenance treatment in patients with schizophrenia. Am J Psychiatry 2010; 167:181–189 Link, Google Scholar FiguresReferencesCited byDetailsCited byNone Volume 167Issue 7 July 2010Pages 868-868 Metrics PDF download History Accepted 1 April 2010 Published online 1 July 2010 Published in print 1 July 2010