Clozapine is licensed for treatment-resistant schizophrenia and when clozapine is not able to be used, less evidence based practices may be required. Full remission may require combinations or high doses of psychotropic medications having greater potential for interactions and side effects. If this is not successful, symptoms may persist and long-term disability may occur.

To explore safety and efficacy of a rechallenge of clozapine in a patient with treatment resistant schizoaffective disorder, who previously developed pericardial effusion. Collateral history reported best improvement with clozapine compared to other medications.

To improve level of functioning and reduce need for less evidence based choices of medication.

Initial consultation with clozapine monitoring service over prospects of rechallenge. Full medication history and review. Consultation with a cardiologist regarding validity of local monitoring strategy. Obtain consent from the patient and his family. Titrate clozapine slowly. Once clozapine initiated, measure temperature, blood pressure, pulse rate and monitoring of symptoms of pericarditis including chest pain, cough and dyspnoea daily. ECG and echocardiography at baseline and 2 and 4 weeks after initiation of the rechallenge. ECGs monthly thereafter, with a further echocardiogram at 3 months. Weekly troponin and CRP for three months to monitor developing myocarditis and pericarditis.

Successful rechallenge of clozapine with significant reduction in psychopathology, improvement in functioning and no adverse events reported. Reduction of risk enabled transfer to open ward conditions.

There is increasing evidence of successful rechallenges of clozapine however, further research is necessary to aid such clinical decisions.

The authors have not supplied their declaration of competing interest.