Risperidone and Metabolite

Risperdal Level

Test Codes

EPIC: LAB1232157, Beaker: RISPERIDONE, Quest: 2339

NOTE: Test includes: Risperidone, OH-Risperidone, Risperidone + OH-Risperidone

Department

Send Outs

Specimen Collection Criteria

Collect: One plain Red-top tube.

Do not use Serum Separator Tubes.

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to plastic transport tube and maintain at room temperature (20-26°C or 68-78.8°F) prior to transport.

Preparation for Courier Transport

Transport: 3.0 mL serum, at room temperature (20-26°C or 68-78.8°F). (Minimum: 1.5 mL)

Rejection Criteria

• Serum Separator (SST) tubes.
• Specimens not collected and processed as indicated.

In-Lab Processing

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to plastic transport tube and maintain at room temperature (20-26°C or 68-78.8°F).

Transport: 3.0 mL serum, at room temperature (20-26°C or 68-78.8°F). (Minimum: 1.5 mL)

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 7 days
Refrigerated (2-8°C or 36-46°F): 31 days
Frozen (-20°C/-4°F or below): 60 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.

Laboratory

Sent to Quest Diagnostics, Wood Dale, IL.

Performed

Tuesday, Thursday, Saturday.
Results available in 1-4 days.

Reference Range

Mean steady-state serum levels of Risperidone + OH-Risperidone following daily regimens

2 mg/day	14.0 ng total active drug/mL
6 mg/day	45.0 ng total active drug/mL
10 mg/day	73.0 ng total active drug/mL
16 mg/day	110.0 ng total active drug/mL

Risperidone and OH-Risperidone are approximately equally effective; therefore, the sum of their concentrations are reported as total active drug.

Test Methodology

Chromatography / Mass Spectrometry

CPT Codes

80299

Contacts

Last Updated

12/19/2025