Will Risperdal Be Detected on a Drug Test the Next Day?
Standard drug screening panels do not test for risperidone (Risperdal), so it will not be detected on routine drug tests performed the next day or at any time. 1
Why Risperidone Is Not Detected on Standard Drug Tests
Risperidone is not included in standard drug screening panels, which typically test for substances of abuse such as opioids, benzodiazepines, amphetamines, cocaine, marijuana (THC), and phencyclidine (PCP). 1
Date-rape drugs and many prescription medications are specifically excluded from standard drug-screening panels, and healthcare professionals must specifically request testing for suspected drugs if they want them detected. 1
Standard immunoassay drug tests are designed to detect illicit substances and commonly abused medications, not antipsychotic medications like risperidone. 1
Pharmacokinetic Considerations (If Specialized Testing Were Ordered)
While not relevant to standard drug screening, if specialized testing for risperidone were specifically requested:
Risperidone reaches peak plasma concentrations approximately 1 hour after oral administration and has a half-life of about 3 hours in extensive metabolizers (most people) or 19 hours in poor metabolizers. 2, 3
The active metabolite 9-hydroxyrisperidone has a half-life of approximately 20 hours in both extensive and poor metabolizers, meaning the drug and its active metabolite would be detectable in blood or urine for several days if specialized testing were performed. 3, 4
Steady-state concentrations are reached within 1 day for risperidone and within 5 days for the active fraction (risperidone plus 9-hydroxyrisperidone). 3
Important Clinical Context
Clinicians should be familiar with which drugs are included in their facility's drug testing panels and understand that a negative standard drug screen does not rule out the presence of prescription medications like risperidone. 1
Specialized testing would require specific laboratory requests and would not be part of routine employment, legal, or clinical drug screening. 1