Lamotrigine by immunoassay
Clinical details: 
Lamotrigine (Lamictal) was first licensed for use as an anti-convulsant in 1994 for the treatment of partial seizures. It has now been licensed for use in monotherapy in adults and children, for both partial and primary and secondary tonic-clonic seizures. Lamotrigine is also widely used as a mood stabiliser in bipolar disorders. The measurement of lamotrigine levels is useful for tailoring treatment for an individual, particularly if poor compliance or toxicity are suspected. The half life of lamotrigine is around 25 hours, but this is significantly affected by many other drugs, especially other anti-convulsants such as carbamazepine, valproate and phenytoin. Large inter-individual variations in the dose/concentration exist and there is a therapeutic range in which lamotrigine is effective and unlikely to lead to severe side effects. Lamotrigine toxicity presents in a similar way to carbamazepine, and therapeutic drug monitoring can help in this diagnosis.
Reference range: 

2.5 - 15 mg/L

Synonyms or keywords: 
Lamictal, lamo,
Sample type and Volume required: 
2mL whole blood collected in EDTA or heparin tube, or 1 mL plasma or serum (pre-dose or ‘trough’ sample)
Turnaround time: 
5 working days
Storage and transport: 
Please refrigerate (if possible) if not sending immediately. Send by first class post.
Toxicology Department at King's Hospital
020 3299 5881
King's College Hospital
Bessemer Wing - 3rd Floor
Denmark Hill
London SE5 9RS
For clinical advice or interpretation of results, please contact the laboratory in the first instance.

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Last updated: 10/11/2022