Quetiapine XR-induced neutropenia: is a clozapine trial still possible for treatment-resistant schizophrenia? A case report

Aim Our case report addresses the use of clozapine in patients who have a history of quetiapine XR‐induced neutropenia. There are no current guidelines for this situation. Methods We present the case of a young woman treated with clozapine at a first‐episode psychosis clinic after a moderate quetiapine XR‐induced neutropenia (0,5–1,0 × 109 L−1). Results The patient was successfully treated with clozapine and lithium, with less psychotic symptoms and a better level of functioning. The neutrophil count remained normal during the treatment period, which has been longer than a year. Conclusion The outcome of this case supports the notion that clinicians could consider introducing clozapine in treatment‐refractory patients who have a history of quetiapine XR‐induced neutropenia, with close blood monitoring. Lithium co‐administration may play a role in maintaining a normal neutrophil count.