Efficacy, tolerability, and kinetics of lamotrigine in infants.
OBJECTIVE
To investigate the efficacy, tolerability, and kinetics of lamotrigine during the first year of life.


METHODS
We studied 13 infants with intractable seizures; 7 had partial seizures and 7 had infantile spasms (1 had both). Patients received open-label lamotrigine as add-on therapy for 3 months. Seizure frequency, response ratio, and side effects score were determined and compared with the baseline period.


RESULTS
The rate of partial seizures per day decreased from 8.57 +/- 2.29 to 4.00 +/- 2.15 (P =.027) and infantile spasms from 8.71 +/- 2.15 to 3.61 +/- 2.762 (P =.028). Apparent clearance increased during the first year of life, with a break point at 2 months of age (mean, 0.119 +/- 0.021, 0.217 +/- 0.094 L/h per kilogram for infants <2 months and those 2 to 12 months old, respectively,P <.001). Twenty-four-hour concentration to time plots of three 3- to 4-week-old neonates showed a half-life of 23.44 +/- 3.57 hours. Compared with a group of 17 older children, LTG had similar efficacy (response ratios, -0.68 +/- 0.12 and -0.74 +/- 0.11, P =.504), and similar adverse effects scores (0.67 +/- 0.67 and 0.23 +/- 0.166, P =.95).


CONCLUSIONS
Lamotrigine is a useful and well tolerated drug for partial seizures and infantile spasms in infants <1 year of age. However, lamotrigine has age-dependent kinetics that must be taken into consideration.
Mikati
Mohamad A
MA
Department of Pediatrics, Adult and Pediatric Epilepsy Program, American University of Beirut, New York City, New York 10022, USA.
Fayad
Michel
M
Koleilat
Majed
M
Mounla
Nabil
N
Hussein
Rania
R
Kazma
Alia
A
Yunis
Khalid
K
D000367:Age Factors; D000927:Anticonvulsants / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D004828:Epilepsies, Partial / Q000188:drug therapy*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D000077213:Lamotrigine; D016014:Linear Models; D008657:Metabolic Clearance Rate; D013036:Spasms, Infantile / Q000188:drug therapy*; D018709:Statistics, Nonparametric; D014227:Triazines / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*
D000927:Anticonvulsants; D014227:Triazines; D000077213:Lamotrigine