Olanzapine: Are Extrapyramidal Symptoms as Rare as We Think? – A Case Series

Olanzapine, a second-generation antipsychotic has proven to be very efficacious with a low probability of extrapyramidal symptoms (EPS). Here, we wish to report a series of cases where EPS is occurring as a rare side effect due to olanzapine. Such reporting is important as these rare side effects could be confused with other clinical pictures, thereby affecting the management. Case 1 describes a 29-year-old woman with bipolar affective disorder who developed dystonic upward deviation of eyes after taking olanzapine 5 mg. Symptoms remitted within 30 min of injection of promethazine 25 mg. Case 2 describes a 21-year-old male with schizophrenia on olanzapine 15 mg, who presented with a complaint of gradual onset excessive blinking of eyes (blepharospasm). A provisional diagnosis of olanzapine-associated tardive blepharospasm was made based on clinical history and physical examination. On injection of promethazine 25 mg, there was remission of blepharospasm. After 2 weeks of discontinuation of olanzapine, there was resolution of blepharospasm. Case 3 describes a 52-year-old male with schizophrenia on olanzapine 25 mg and trihexyphenidyl 2 mg who presented with a complaint of gradual onset chewing movements and clenching of his jaw for the past 6 months. A provisional diagnosis of olanzapine-associated tardive dyskinesia was made based on clinical history and physical examination. Tablet olanzapine was tapered down slowly to 15 mg. After 4 weeks, the Abnormal Involuntary Movement Scale (AIMS) score showed improvement, so olanzapine was cross-tapered with aripiprazole. After 3 months, the movements had significantly reduced. Reporting such rare side effects is necessary as it can help in appropriate identification as well as prevent confusion with other clinical pictures. Through this, it can positively help in the correct line of management besides enhancing our knowledge of how atypical antipsychotics can lead to the development of extrapyramidal symptoms.