LAMITOR Tablet Ref.[50455] Active ingredients: Lamotrigine

Lamotrigine is rapidly and completely absorbed from the gut. The absorption is unaffected by food. The time to peak concentration is 1,4 to 4,8 hours. The mean elimination half-life is 25 ± 10 hours and the pharmacokinetic profile is linear up to 450 mg, the highest single dose tested. The half-life of lamotrigine is affected by concomitant use of enzyme-inducing drugs such as phenytoin, carbamazepine, phenobarbital or primidone with a mean value of approximately 14 hours.

The half-life of lamotrigine increases to approximately 59 hours when co-administered with valproic acid alone (see DOSAGE AND DIRECTIONS FOR USE). Following multiple administration of lamotrigine (150 mg twice daily) there is modest induction of its own metabolism, resulting in a 25% decrease in the elimination half-life at steady state. Lamotrigine is moderately (55%) bound to plasma proteins. Clearance adjusted for bodyweight is higher in children aged 12 years and under than in adults, with the highest values in children under 5 years. The half-life of lamotrigine is generally shorter in children than in adults with a mean value of approximately 7 hours when given with enzyme-inducing drugs such as carbamazepine and phenytoin.