The PRAC has updated recommendations for blood monitoring in patients treated with clozapine. This medicine, indicated for treatment-resistant schizophrenia and psychotic disorders in Parkinson's disease, may increase the risk of neutropenia (reduction in neutrophils) and agranulocytosis.

To minimize this risk, regular blood count monitoring is recommended, now simplified and based exclusively on the absolute neutrophil count (ANC), considered the most reliable parameter.

In summary, the new recommendations include:

• Treatment thresholds: ANC ≥ 1,500/mm³ in the general population; ANC ≥ 1,000/mm³ in patients with benign ethnic neutropenia (BEN).
• Monitoring frequency: weekly during the first 18 weeks, monthly until the end of the first year, then every 12 weeks; after two years of stable treatment without episodes of neutropenia, monitoring may be performed annually.

The risk of neutropenia is highest during the first year of therapy and subsequently tends to decrease. The new indications will be updated in the product information of clozapine containing medicines.
The related document provides further information.