Test ID QUIND Quinidine, Serum
Useful For
Assessing and adjusting dosage for optimal therapeutic level
Assessing toxicity
Method Name
Kinetic Interaction of Microparticles in Solution (KIMS)
Reporting Name
Quinidine, SSpecimen Type
Serum RedContainer/Tube: Red top
Specimen Volume: 0.5 mL
Collection Instructions: Red-top tubes should be centrifuged and aliquoted within 2 hours of collection.
Specimen Minimum Volume
0.25 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Serum Red | Refrigerated (preferred) | 14 days |
Frozen | 28 days | |
Ambient | 14 days |
Clinical Information
Quinidine is indicated for atrial fibrillation and flutter, and life-threatening ventricular arrhythmia. Optimal serum concentrations are in the range of 2.0 to 5.0 mcg/mL, with toxicity apparent at levels ≥6.0 mcg/mL. Symptoms of toxicity (cinchonism) include tinnitus, light-headedness, premature ventricular contractions, and atrioventricular block. Gastrointestinal distress is a frequent side effect, which becomes more severe and is associated with nausea and vomiting at higher drug concentrations.
The half-life of quinidine is 6 to 8 hours, and the drug lacks any significant active metabolites. Physiologic processes that generally reduce hepatic metabolism and renal clearance increase serum quinidine levels, while comedication with cytochrome p450 (CYP) enzyme inducers enhances clearance and results in lower blood concentrations.
Reference Values
Therapeutic: 2.0-5.0 mcg/mL
Critical value: ≥6.0 mcg/mL
Cautions
No significant cautionary statements.
Day(s) Performed
Monday through Sunday; Continuously
Report Available
Same day/1 dayPerforming Laboratory

Test Classification
This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
80194