ABSTRACT
Background & objectives: Though newer antiepileptic drugs are considered safer than conventional antiepileptics, the effects of lamotrigine, levetiracetam and topiramate on neurobehavioural functions are yet to be established. This study evaluated neurobehavioural parameters and oxidative stress markers in brain tissue of rats treated with lamotrigine, levetiracetam and topiramate compared to sodium valproate . Methods: Five groups of male Wistar rats were treated respectively with normal saline (control), sodium valproate (370 mg/kg), lamotrigine (50 mg/kg), levetiracetam (310 mg/kg) and topiramate (100 mg/kg) for 45 days. Neurobehavioural parameters were assessed using elevated plus maze (EPM), actophotometer, rotarod, passive avoidance and Morris water maze (MWM) at baseline and at the end of treatment. Oxidative stress parameters [malondialdehyde (MDA), reduced glutathione (GSH) and superoxide dismutase (SOD)] were estimated in rat brain at the end of treatment. Results: Valproate and lamotrigine showed no significant effect on learning and memory in passive avoidance and MWM tests. However, levetiracetam and topiramate reduced retention memory significantly as compared to control (P<0.01) and lamotrigine (P<0.05) groups. Performances on EPM, rotarod and actophotometer were not significantly different between the groups. In comparison to control group, MDA was higher in the levetiracetam and topiramate (360.9 and 345.9 nmol/g of homogenized brain tissue, respectively) groups. GSH and SOD activity were significantly reduced by valproate and levetiracetam treatment. Lamotrigine did not induce significant oxidative stress. Interpretation & conclusions: Long-term and therapeutic dose treatment with levetiracetam and topiramate significantly impaired learning and memory, which was not seen with valproate and lamotrigine in rats. Levetiracetam, topiramate and valproate augmented oxidative stress, whereas lamotrigine has little effect on it. These antiepileptic drugs are used in clinical practice, hence pharmaco- vigilance studies are required to evaluate their safety profile.
ABSTRACT
Background & objectives: Certain antiepileptic drugs (AEDs) such as valproic acid (VPA) are known to affect body weight, and lipid profile. However, evidences regarding effects of AEDs on the body composition are deficient. This cross-sectional study compared the body composition and lipid profile among patients with epilepsy on newer and conventional AEDs. Methods: The patients with epilepsy (n=109) on treatment with conventional and newer AEDs (levetiracetam, lamotrigine and clobazam) for > 6 months were enrolled. Of these, 70 were on monotherapy: levetiracetam (n=12), VPA (n=16), carbamazepine (n=20) and phenytoin (n=22) and the remaining on polytherapy. Their body composition [body fat mass, lean dry mass (LDM), total body water (TBW), intracellular water (ICW), extracellular water (ECW) and basal metabolic rate (BMR) was estimated and biochemical parameters were assessed. Results: Levetiracetam group had no significant difference with VPA, carbamazepine, phenytoin and control groups, except low LDM (17.8±2.4) than VPA groups (20.2±2.7, P<0.05). In comparison with control, AEDs monotherapy groups had no significant difference, except higher LDM and ECW in VPA group. Among groups based on conventional and newer AEDs, there was no significant difference in body composition parameters except for higher LDM (as % of BW) in conventional AEDs only treated group than control (P<0.01). Interpretation & conclusions: The alterations observed in body composition with valproic acid in contrast to other AEDs like levetiracetam, carbamazepine and phenytoin could affect treatment response in epilepsy especially in subjects with already altered body composition status like obese and thin frail patients, which needs to be established by prospective studies (CTRI/2013/05/003701).