TY - JOUR

T1 - Paliperidone poisoning and measurable plasma concentrations 2.5 years after last administered dose

T2 - A case report

AU - Nersesjan, Mariam

AU - Wagner, Maria

AU - Dalhoff, Kim Peder

AU - Petersen, Tonny Studsgaard

AU - Bøgevig, Søren

AU - Horwitz, Henrik

N1 - Publisher Copyright: © 2024 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

PY - 2024

Y1 - 2024

N2 - We report a poisoning with paliperidone palmitate, a once-monthly, long-acting injectable antipsychotic. The patient suffered from deep sedation and dystonia. She had been treated with extended release intramuscular paliperidone for several years and had received her last injection 8 days prior to admission. The plasma paliperidone was nearly five times higher than the upper reference range. Paliperidone is a substrate of p-glycoprotein and we therefore aimed to increase its elimination by inducing p-glycoprotein through treatment with St John's wort. This seemed to have a limited effect on paliperidone clearance. Plasma concentration levels decreased with time as did the dystonia. All antipsychotic treatment was discontinued after this unfortunate event, and the patient did specifically not receive any prescriptions of paliperidone or risperidone. However, the plasma paliperidone concentration was in the low end of the normal therapeutic range 2.5 years after the last dose of paliperidone was administered, and the patient still had some extrapyramidal symptoms.

AB - We report a poisoning with paliperidone palmitate, a once-monthly, long-acting injectable antipsychotic. The patient suffered from deep sedation and dystonia. She had been treated with extended release intramuscular paliperidone for several years and had received her last injection 8 days prior to admission. The plasma paliperidone was nearly five times higher than the upper reference range. Paliperidone is a substrate of p-glycoprotein and we therefore aimed to increase its elimination by inducing p-glycoprotein through treatment with St John's wort. This seemed to have a limited effect on paliperidone clearance. Plasma concentration levels decreased with time as did the dystonia. All antipsychotic treatment was discontinued after this unfortunate event, and the patient did specifically not receive any prescriptions of paliperidone or risperidone. However, the plasma paliperidone concentration was in the low end of the normal therapeutic range 2.5 years after the last dose of paliperidone was administered, and the patient still had some extrapyramidal symptoms.

KW - antipsychotic medicine

KW - therapeutic drug monitoring

KW - toxicology

U2 - 10.1111/bcp.16036

DO - 10.1111/bcp.16036

M3 - Journal article

C2 - 38450747

AN - SCOPUS:85186939389

JO - British Journal of Clinical Pharmacology, Supplement

JF - British Journal of Clinical Pharmacology, Supplement

SN - 0264-3774

ER -