Successful rechallenge with clozapine after treatment associated eosinophilia

Objective: Eosinophilia has been associated with the use of clozapine. Where clozapine associated eosinophilia develops, and is associated with organ specific damage, clozapine is usually ceased. In cases of treatment associated eosinophilia without evidence of organ specific damage, clozapine would also typically be withdrawn. There are small numbers of reports in the literature describing patients who have had a successful rechallenge of clozapine having previously stopped treatment due to eosinophilia without associated organ specific inflammation. We report the case of a man who underwent a successful retrial of clozapine.

Method: Case from authors' clinical practice reviewed.

Results: We present the case of a young man with treatment resistant schizophrenia who underwent a successful re-challenge of clozapine, having previously ceased treatment due to an eosinophilia associated with treatment.

Conclusion: We believe that the current report provides further evidence that it may be unnecessary to cease treatment in all patients who develop an eosinophilia without organ dysfunction whilst on clozapine. Furthermore, where clozapine has been ceased due to an eosinophilia without evidence of organ specific inflammation, clozapine rechallenge with increased haematological monitoring should be considered.