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Treatment resistant schizophrenia – review and a call to action

  • J. Lally (a1) (a2) (a3) (a4) and F. Gaughran (a1) (a5)

Recovery rates in schizophrenia remain suboptimal with up to one-third resistant to standard treatments, a population prevalence of 0.2%. Clozapine is the only evidenced-based treatment for treatment resistant schizophrenia (TRS), yet there are significant delays in its use or it may not be trialled, potentially impacting the chance of recovery. Better outcomes with earlier use of clozapine may be possible. There is emerging evidence that early treatment resistance is not uncommon from the earliest stages of psychosis. In this review, we provide an update on TRS, its epidemiology and its management, with a specific focus on the optimal use and timing of clozapine and augmentation strategies for the one-third of patients who do not respond to clozapine.

Corresponding author
*Address for correspondence: Dr John Lally, PO63, Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London, De Crespigny Park, London SE5 8AF, UK. (Email:
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Irish Journal of Psychological Medicine
  • ISSN: 0790-9667
  • EISSN: 2051-6967
  • URL: /core/journals/irish-journal-of-psychological-medicine
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