Prevalence of Lower-Than-Expected Plasma Levels in Medicated Patients Presenting for Acute Psychiatric Inpatient Treatment

Noncompliance or incomplete compliance with psychopharmacological medication by psychiatric patients is a frequent risk, prevalence rates ranging from 18 to 70% (numerical mean, 44%). However, many of the previously used methods to determine compliance (e.g. questionnaires, pill counts or colouring additives for qualitative detection in urine) might underreport actual rates of non-adherence to treatment.