Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.
In-home collection may be available in your area for purchase through Quest Mobile.
Clinical Significance
Leflunomide Metabolite - Leflunomide is an immunosuppressant medication used in the treatment of rheumatoid arthritis. Leflunomide is rapidly and extensively metabolized to teriflunomide, which is the active form of the medication. Steady state plasma concentrations in patients receiving recommended daily dosages: up to 63,000 ng/mL. It is recommended that all women of childbearing potential who discontinue leflunomide and women receiving treatment who wish to become pregnant undergo the cholestyramine drug elimination procedure. This procedure includes verification that plasma levels of teriflunomide are less than 20 ng/mL by two separate tests at least 14 days apart.
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Reference Range(s)
Mean steady state plasma concentrations of teriflunomide from patients on daily dosages of 5, 10, or 25 mg of leflunomide were 8,800, 18,000 and 63,000 ng/mL, respectively. It is recommended that women of childbearing potential who discontinue leflunomide therapy undergo the cholestyramine drug elimination procedure. This procedure includes verification that plasma levels of teriflunomide are less than 20 ng/mL by two separate tests at least 14 days apart.
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Reference Range(s)
Mean steady state plasma concentrations of teriflunomide from patients on daily dosages of 5, 10, or 25 mg of leflunomide were 8,800, 18,000 and 63,000 ng/mL, respectively. It is recommended that women of childbearing potential who discontinue leflunomide therapy undergo the cholestyramine drug elimination procedure. This procedure includes verification that plasma levels of teriflunomide are less than 20 ng/mL by two separate tests at least 14 days apart.
Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.
In-home collection may be available in your area for purchase through Quest Mobile.