This study aims to describe the course of admission and clinical characteristics of admissions to a psychiatric intensive care unit (PICU) in the Phoenix Care Centre (PCC), Dublin, Ireland.

This retrospective chart study was conducted at the PCC, Dublin, Ireland. The cohort included all admission episodes (n = 91 complete data) over a three-year study period between January 2014 and January 2017.

The mean age of admitted cases was 37.1 (s.d. = 11.3; range 18–63). The mean length of stay (LOS) was 59.3 days (s.d. = 61.0; median 39.5 days). All patients were admitted under Mental Health Act legislation. Antipsychotic polypharmacy was used in 61% (n = 55) of the admissions. A diagnosis of acute psychotic disorder (B = −1.027, p = 0.003, 95% CI: −1.691, −0.363) was associated with reduced LOS in PICU.

Our study describes the cohort of patients admitted as being predominantly male, younger-aged, single, having a diagnosis of schizophrenia and being legally detained. The primary indication for referral is risk of assault, which highlights the need for the intensive and secure treatment model that a PICU can provide.