Safe to stop monthly blood tests for clozapine after two years: Aussie study

The risk of severe neutropenia becomes 'negligible' two years after initiating treatment, doctors say.

Most patients given clozapine for schizophrenia can stop monthly blood tests after two years, according to Australian psychiatrists who say the current practice of indefinite monitoring is unnecessary.

The University of Queensland-led team found that the risk of serious neutropenia leading to clozapine cessation peaked in the first 18 weeks of starting treatment and became “negligible” after two years.

As a result, they said monthly absolute neutrophil count (ANC) monitoring could safely be stopped after the two-year mark unless clinically indicated.

“We hope this study will provide the basis for a change in practice, making clozapine more accessible to those who need it and improving the lives of people on the drug,” said senior author Professor Dan Siskind.