Olanzapine-Induced Obsessive-Compulsive Disorder

Mr. A began treatment for schizophrenia in 1994. He received a dose of risperidone (at 3–6 mg/day) for a year. No symptoms of OCD were noted during this time. However, intensive evaluation revealed that since childhood, Mr. A had periodically felt himself driven to say obscene words. Such episodes were isolated and not a part of OCD or Tourette’s disorder, nor were they exacerbated by risperidone. In 1998, treatment was changed to a dose of olanzapine (at 15 mg/day) because of akathisia and persistent psychotic symptoms. Both disappeared, but 14 days after starting to take olanzapine, he developed a clear OCD, repeating words in his head and spending a tremendous amount of time checking doors. These OCD symptoms disappeared with fluoxetine; therefore, olanzapine treatment could be continued unchanged.

Mr. B, a 27-year-old man, had been treated for schizophrenia since 1994. Risperidone was introduced after an acute episode in 1997 and increased to a dose of 8 mg/day. Five months later he was switched to olanzapine, up to 25 mg/day, because of persistent psychotic symptoms. Mr. B never previously complained of symptoms related to OCD. Within 3 months he demonstrated a clear OCD, isolating himself, washing repeatedly, checking doors and the alarm system, as well as suffering from impulsion phobias. However, he had no recurrence of psychotic symptoms. Once treated with a regimen of clomipramine, at 150 mg/day, Mr. B experienced a remarkable reduction of OCD symptoms.