ARK™ Lamotrigine Assay

The ARK™ Lamotrigine Assay is a homogeneous enzyme immunoassay intended for the quantitative determination of lamotrigine in human serum or plasma on automated clinical chemistry analyzers. The measurements obtained are used in the monitoring of lamotrigine levels to help ensure appropriate therapy.

Assay Characteristics

  • Excellent precision, even in trough concentrations
  • Fast and efficient routine monitoring for lamotrigine
  • Liquid, ready-to-use reagents, calibrators and controls
  • Storage at 2-8°C
  • On-board stability for at least 60 days
  • Does not contain any harmful preservatives, only ≤ 0.09% sodium azide

Background

Lamotrigine (LAMICTAL®, 3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazine) is an anti-convulsant drug approved for use in the treatment of epilepsy and is often prescribed as monotherapy or as one component of a multiple anti-epileptic drug therapy.

A therapeutic range for lamotrigine has not been well established. Some reports in the literature suggest a target range for steady-state concentrations of 3 to 15 μg/mL. However, there is not a clear relationship between lamotrigine serum concentrations and clinical response. Due to individual patient differences and other co-administered medications, considerable overlap in lamotrigine concentrations has been observed between serum responders and non-responders as well as between serum levels associated with seizure control and adverse effects. In one study, the highest mean serum level (trough) reported was 8.8 μg/mL, and less than 15% of patients reported an adverse event at serum concentrations less than 10 μg/mL. Mild to moderate adverse effects are more commonly associated with patients with lamotrigine concentrations above 15 μg/mL.