Clozapine rechallenge A clozapine "rechallenge" is when someone that experienced agranulocytosis while taking clozapine starts taking the medication again. In countries in which the neutrophil thresholds are higher than those used in the US a simple approach is, if the lowest ANC had been above the US cut off, to reintroduce clozapine but with the US monitoring regime. This has been demonstrated in a large cohort of patients in a hospital in London in which it was found that of 115 patients who had had clozapine stopped according to the US criteria only 7 would have had clozapine stopped if the US cut offs had been used. Of these 62 were rechallenged, 59 continued to use clozapine without difficulty and only 1 had a fall in neutrophils below the US cut off. Other approaches have included the use of other drugs to support neutrophil counts including lithium or granulocyte colony-stimulating factor (G-CSF). However, if agranulocytosis still occurs during a rechallenge, the alternative options are limited.
clozapine rechallenge a clozapine "rechallenge" is when someone that experienced agranulocytosis while taking clozapine starts taking the medication again in countries in which the neutrophil thresholds are higher than those used in the us a simple approach is if the lowest anc had been above the us cut off to reintroduce clozapine but with the us monitoring regime this has been demonstrated in a large cohort of patients in a hospital in london in which it was found that of 115 patients who had had clozapine stopped according to the us criteria only 7 would have had clozapine stopped if the us cut offs had been used of these 62 were rechallenged 59 continued to use clozapine without difficulty and only 1 had a fall in neutrophils below the us cut off other approaches have included the use of other drugs to support neutrophil counts including lithium or granulocyte colony-stimulating factor (g-csf) however if agranulocytosis still occurs during a rechallenge the alternative options are limited