Clozapine, an atypical antipsychotic agent commonly used for treatment-resistant schizophrenia (TRS) is well known to cause blood dyscrasias among many other common side effects like sedation, sialorrhoea, weight gain and some rare side effects such as eosinophilia. Clozapine-induced eosinophilia though rare has received extensive attention and may preclude its use in the patients who may otherwise be responding well to the treatment. Although there has been evidence in the literature highlighting the rare presentation of eosinophilia in patients receiving clozapine. Here we present a rare case of undifferentiated schizophrenia who received clozapine in the past and tolerated it well but developed transient eosinophilia on its re-introduction.
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