Rechallenge with clozapine following leucopenia or neutropenia during previous therapy

Abstract

No clear risk factor for repeat blood dyscrasias was identified. Despite this, after risks and benefits have been considered, rechallenge may well be justified in some patients.

Haematological toxicity of drugs used in psychiatry

“…Furthermore, in some patients the risks of withholding treatment may be greater than the risk of rechallenge, and although overall rechallenge patients are 22 times more likely to develop agranulocytosis than clozapine-naïve subjects, the risk may be justified on occasion (Silvestrini et al, 2000). Demographic, haematological and outcome data of 53 patients (UK and Ireland) who were rechallenged with clozapine following leucopenia or neutropenia during previous clozapine therapy, but in whom it was felt that it was likely that the dyscrasia was not clozapine-induced, have been presented (Dunk et al, 2006). Twenty (38%) patients experienced a further blood dyscrasia (post-2002 criteria-see Table 7).…”

“…There is likely to be an immune component since the reaction occurs more quickly and is more severe on rechallenge in patients who have developed clozapineinduced neutropenia (Dunk et al, 2006).…”

Allergic Cutaneous and Visceral Angioedema Secondary to Clozapine: A Case Report

“…Rechallenge of clozapine has been reported in the case of clozapineinduced leucopenia (Dunk et al 2006;Stanulovic et al 2013). However, there is no literature which discussed rechallenging clozapine in the case of allergic reaction.…”

Continuation of clozapine during chemotherapy and a stem cell transplant

“…However, one study has shown that of 53 patients rechallenged with clozapine following an initial blood dyscrasia, 38% developed a further leucopenia or neutropenia. 11 Clozapine has been shown to activate some of the same apoptic pathways as chemotherapy, 12 but it is not clear if concurrent use has an additional harmful effect. 13 In many of the available case reports where neutropenia did occur, granulocyte-colony stimulating factor (G-CSF) was used to help increase white cell counts.…”