NHS Greater Glasgow & Clyde Area Drug and Therapeutics Committee
Greater Glasgow and Clyde Medicines
Medicines Update

Clozapine and Cytotoxic Treatment

Updated July 2020

Key messages

  • The side effect profile of clozapine means it is subject to mandatory processes and monitoring which are intended to ensure patient safety
  • Concurrent use of medications known to cause neutropenia are contraindicated with clozapine
  • In the event of an individual prescribed clozapine requiring cytotoxic treatment, a special treatment plan must be established to manage the contraindicated combination and allow clozapine treatment to continue

The use of clozapine in combination with other drugs that can cause myelosuppression is contraindicated. In the event of a patient prescribed clozapine needing to undergo treatment with a cytotoxic agent e.g. chemotherapy treatment for cancer, a treatment plan must be established in consultation with mental health services, the clozapine monitoring service and the specialist oncology service to support the use of the contraindicated combination and allow clozapine to continue whilst undergoing chemotherapy. This treatment plan will usually involve increased FBC monitoring and altering the standard FBC parameters used for monitoring clozapine. Click here for further advice on managing clozapine and other medicines known to cause myelosuppression,


Originally published 10/09/18 and updated on 28/07/20. Medicines Update blogs are correct at the time of publication