Čes. slov. farm. 2023, 72(6):276-286 | DOI: 10.5817/CSF2023-6-276

Potential impact on mental health in patients with treatment-resistant schizophrenia - clozapine augmentation with long-acting parenteral antipsychotics: a case series

Martina Nováková^1,2, Tomáš Hammer^1,3, Eliška Nováková¹, Michaela Mayerová⁴, Libor Ustohal^1,4, Hana Kotolová^1,*

¹ Ústav farmakologie a toxikologie, Farmaceutická fakulta, Masarykova univerzita, Brno

² Ústav aplikované farmacie, Farmaceutická fakulta, Masarykova univerzita, Brno

³ Farmakologický ústav, Lékařská fakulta, Masarykova univerzita, Brno

⁴ Psychiatrická klinika Lékařské fakulty Masarykovy Univerzity a Fakultní nemocnice Brno

Introduction: The rate of pharmacoresistance among in patients diagnosed with schizophrenia is around 30%. Clozapineis the drug of choice for these patients; however, an adequate response to treatment doesn't always occur. One of the possible augmentation approaches, specifically for non-adherent patients, is the administration of long-acting parenteral antipsychotics. Our goal was to evaluate previous experiences of administering a combination of the atypical antipsychotic clozapine and long-acting injectable antipsychotics to pharmacoresistant patients at the Department of Psychiatry the Czech Republic and to assess the safety and effectiveness of such administration.

Methods: A retrospective evaluation of patient case studies was conducted for those who were hospitalized in the Ward for the therapy of Psychotic disorders between 2016 and 2020 and had a medication history of combining clozapine and depot antipsychotics.

Results: Over half of the patients had no illness relapses during the observed period. The clinical manifestation of adverse effects from combination therapy appears low in our patient sample, primarily involving mild and pharmacologically manageable side effects (tachycardia). Only one of the cases recorded neutropenia, which led to discontinuation of clozapine; the patient was maintained on long-acting injectable antipsychotics medication.

Conclusion: From our findings, it can be inferred that augmenting clozapine with depot antipsychotics is a potential therapeutic intervention that pharmacoresistant patients could benefit from. However, it is essential to emphasize that this therapeutic approach should only be administered after carefully considering the patient's existing treatment. It should be strictly individualized based on the treating physician's or clinical pharmacist's sufficient professional experience.

Keywords: pharmacoresistance; Schizophrenia; clozapine; long-acting antipsychotics; nonadherence

Received: August 14, 2023; Accepted: October 16, 2023; Published: June 1, 2023  Show citation