Changing manufacturer to address neutropenia induced by non-clozapine second-generation antipsychotics: Changing antipsychotic manufacturer to address neutropenia.

BACKGROUND

Clozapine is the antipsychotic most associated with causing neutropenia, a reduction of absolute neutrophil count (ANC) to less than 1500 cells/μL, but neutropenia can also occur with other second-generation antipsychotics (SGAs). Studies suggest that patients who develop clozapine-induced neutropenia may be rechallenged with clozapine after their ANC recovers. However, evidence for rechallenging patients who develop neutropenia with other SGAs is scarce and limited to case reports typically involving switching antipsychotics.

CASE SUMMARIES

Reported are 2 cases in which patients who developed neutropenia with a generic formulation of a non-clozapine SGA were successfully rechallenged with the same antipsychotic from a different manufacturer: one brand name and one alternative generic.

PRACTICE IMPLICATIONS

These cases show how switching to an alternative manufacturer may help resolve neutropenia without changing antipsychotic. Inactive ingredients used by different manufacturers are presented as a potential contribution to the development of neutropenia.