Olanzapine-Induced Thrombocytopenia in a Patient With Chronic Schizophrenia: A Case Report.

Olanzapine, a second-generation antipsychotic widely used for schizophrenia, is primarily known for its efficacy in managing both positive and negative symptoms. While its metabolic side effects are well-documented, hematologic complications such as thrombocytopenia are rare and often underrecognized. A 30-year-old Middle Eastern male with a longstanding history of schizophrenia developed persistent thrombocytopenia after several years of olanzapine use, with platelet counts consistently below the normal range. Despite being asymptomatic for bleeding or bruising, his platelet decline necessitated treatment adjustments. Cross-tapering olanzapine with other antipsychotics initially failed due to psychiatric relapse, but the introduction of aripiprazole alongside olanzapine tapering successfully improved platelet counts while maintaining psychiatric stability. The successful use of aripiprazole in this case represents a novel therapeutic approach, addressing antipsychotic-induced thrombocytopenia without compromising psychiatric outcomes. This case underscores the rare but significant risk of olanzapine-induced thrombocytopenia and highlights the need for vigilant hematologic monitoring during long-term antipsychotic therapy, even in asymptomatic patients or those with low baseline platelet count or concomitant blood dyscrasias.