Test Code VENLA Venlafaxine, Serum
Reporting Name
Venlafaxine, SUseful For
Monitoring serum concentration during therapy
Evaluating potential toxicity
Evaluating patient compliance
Performing Laboratory

Specimen Type
Serum RedSpecimen Required
Collection Container/Tube: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Draw blood immediately before next scheduled dose.
2. Blood drawn from patients 12 hours after an oral dose is also appropriate. It is customary to treat the patient at bedtime with a dose, then, collect specimen the following morning prior to next dose.
3. Centrifuge and remove serum from cells within 2 hours of collection.
Specimen Minimum Volume
0.4 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum Red | Refrigerated (preferred) | 28 days | |
Ambient | 28 days | ||
Frozen | 28 days |
Reference Values
Venlafaxine + O-desmethylvenlafaxine: 195-400 ng/mL
Day(s) and Time(s) Performed
Thursday; 4 p.m.
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
80299
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
VENLA | Venlafaxine, S | 62849-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
83732 | Venlafaxine | 9630-5 |
30195 | O-desmethyl Venlafaxine | 9630-5 |
32182 | Venlafaxine+O-Desmethylvenlafaxine | 62849-5 |
Clinical Information
Venlafaxine is a serotonin and norepinephrine reuptake inhibitor approved for treatment of major depression, anxiety and panic disorders, and social phobias. It is also used for bipolar disorder, bulimia, post-traumatic stress, obsessive behavior, and attention-deficit disorder. Venlafaxine is converted by cytochrome P450 (CYP) 2D6 to the active metabolite, O-desmethylvenlafaxine. The therapeutic range for venlafaxine includes measurement if O-desmethylvenlafaxine; optimal response is seen when combined concentrations of parent and metabolite are between 195 and 400 ng/mL. Venlafaxine is significantly affected by reduced hepatic function, but only slightly by reduced renal function.
Average elimination half-lives are 5 hours for venlafaxine and 10 hours for O-desmethylvenlafaxine, which are much shorter than many other antidepressants. For this reason, extended release formulations are available. Time to peak serum concentration is 2 hours for the regular product and 8 hours for the extended release product. Common toxicities are mild, including drowsiness, dizziness, nausea, and headache.
Analytic Time
1 dayReject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
NY State Approved
YesMethod Name
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Forms
If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.