Antipsychotic Blood Levels, Part 2: Active Moieties, LAIs, and Special Populations

<jats:p>For risperidone TDM, measure both risperidone and paliperidone. Paliperidone (9-hydroxy risperidone) represents about five-sixths of the active moiety. Aripiprazole trough level is approximately 11 times the oral dose. Use this ratio to confirm whether the prescribed dose matches your plasma level target. A subtherapeutic plasma level, in the absence of other explanations, signals non-adherence. When non-adherence is confirmed, strongly consider switching to a long-acting injectable.</jats:p>