To evaluate factors of therapeutic efficacy of paliperidone palmitate, such as the speed of action and its maintenance in patients who experienced a first psychotic episode that led to a hospital admission in the acute unit.

Two-year observational and descriptive study. Patients admitted to the Mental Health Hospital Unit (MHHU) from January 2013 to July 2014, with a first psychotic episode and under paliperidone palmitate treatment. Monitoring and evaluation six months after hospital discharge. They were evaluated using the PANSS and BPRS scales at four different time points of the evolutionary process.

Average scores of the BPRS scale: 39 on admission day, 27 on day of discharge, 23 on the third month and 20 on the sixth month. Average score of PANSS scale: PANSS-PG: 64 on admission day, 48 on day of discharge, 25 on the 3rd month, and 20 on the 6th month. PANSS-P: 41 on admission day, 21 on day of discharge, 12 on the 3rd month, and 10 on the 6th month. PANSS-N: 21 on admission, 11 at discharge, 8 on 3rd month and 7 on 6th month. No clinically significant side effects were observed that would lead to the modification of the doses or the abandonment of the treatment in this period.

The results of this observational study show that the start of the treatment with PAP is associated with an observable clinical response on the 4th day. The evaluation scales at the 3rd and 6th months also suggest the maintenance of efficacy of the treatment.

The authors have not supplied their declaration of competing interest.