CPT® Code 80210

The CPT® Code 80210 refers to a laboratory test specifically designed for the monitoring of therapeutic levels of rufinamide, which is an antiepileptic medication. Rufinamide is primarily utilized in the treatment of seizures associated with Lennox-Gastaut syndrome, a severe form of epilepsy that affects both children and adults, as well as for managing focal seizures in adolescents and adults. The purpose of therapeutic drug monitoring (TDM) is to ensure that the drug levels remain within a therapeutic range, which is crucial for maximizing efficacy while minimizing the risk of toxicity. This monitoring is particularly important for patients who may be taking other medications that could interact with rufinamide or those undergoing hemodialysis, as these factors can significantly influence drug metabolism and clearance. The elimination half-life of rufinamide ranges from 6 to 10 hours, indicating the time it takes for half of the drug to be eliminated from the body, which occurs through hepatic metabolism. Effective management of seizures is associated with mean plasma concentration trough levels of rufinamide between 5.0 and 30 mcg/mL. This range is broad due to individual variability in drug absorption and clearance, as well as the potential impact of co-administered medications. Levels exceeding 30 mcg/mL have been associated with toxicity, which can manifest through various adverse effects, including headache, dizziness, fatigue, nausea, and drowsiness. To accurately assess rufinamide levels, a blood specimen is typically collected just before the next scheduled dose or at least 12 hours after the last dose of a sustained-release formulation. The collected sample must be processed promptly; it is centrifuged to separate the serum from blood cells within two hours of collection and then stored in a plastic vial for analysis. The concentration levels of rufinamide are determined using advanced techniques such as quantitative solid phase extraction-tandem mass spectrometry or quantitative liquid chromatography-tandem mass spectrometry, ensuring precise measurement of the drug in the bloodstream.