Felbamate (Felbatol), Serum
Use
Felbamate is an anticonvulsant drug approved for treatment of partial seizures with or without secondary generalization in persons 14 years and older. It is also approved for Lennox-Gastout syndrome in children 2 years and older. Optimal response to felbamate is seen with serum concentrations between 30 mcg/mL and 80 mcg/mL. It also monitors the concentration levels when co-administered with drugs such as phenytoin or carbamazepine, as these affect felbamate concentration levels, requiring potentially adjusted dosing.
Special Instructions
Draw blood immediately before the next scheduled dose. Within 2 hours of collection, centrifuge the specimen. For red-top tubes, immediately aliquot serum into a plastic vial. For serum-gel tubes, aliquot serum into a plastic vial within 24 hours of collection.
Limitations
Felbamate should not be used in individuals with hepatic disease due to the risk of severe toxicity, including life-threatening aplastic anemia or liver failure. Patients with kidney dysfunction may require reduced dosing. Toxicity is associated with serum concentrations exceeding 100 mcg/mL.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 6899-9
- 6899-9
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
Plastic vial
Collection Instructions
Draw blood immediately before next scheduled dose. Centrifuge within 2 hours of collection, and aliquot serum into a plastic vial.
Causes for Rejection
Gross hemolysis: OK; Gross lipemia: OK; Gross icterus: OK
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 28 days |
| Refrigerated | 28 days |
| Frozen | 28 days |