For Specimen Integrity during Extreme Weather see the “Lockbox Usage in Extreme Weather” document at the top of this page.

Test Code

CPT Codes

Preferred Specimen
1 mL plasma collected in a 3.2% sodium citrate (light blue-top) tube

Patient Preparation
Collect samples 2-4 hours post dose (peak)

Minimum Volume
0.5 mL

Transport Temperature

Specimen Stability
Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 28 days


FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Set up: Mon, Wed, Fri a.m.; Report available: Next day

Reference Range
Peak mcg/L
(at steady state)
Trough* mcg/L
20 mg qD 182-408 3-153
15 mg qD 180-408 2-161
10 mg qD 91-196 1-38
*The lower limit of detection for this assay is 30 mcg/L. The ranges are based on literature references (see FAQs).

Clinical Significance
Rivaroxaban is an oral factor Xa inhibitor that is indicated to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. It is also indicated for the treatment, prophylaxis, or the reduction in the risk of reoccurrence of deep vein thrombosis (DVT) or pulmonary embolism (PE). Rivaroxaban does not need to be monitored routinely, however, exceptions may include determination of failure of therapy vs. poor compliance, or potential dose adjustment required for renal or hepatic dysfunction.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

Last Updated: December 6, 2021

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.