Effects of four antiepileptic drugs on sleep and waking in the rat under both light and dark phases

Effect of oxcarbazepine on sleep architecture

The most common side effects following administration of antiepileptic drugs involve alterations in sleep architecture and varying degrees of daytime sleepiness. Oxcarbazepine is a drug that is approved as monotherapy for the treatment of partial seizures and generalized tonic-clonic seizures. However, there is no information about its effects on sleep pattern organization; therefore, the objective of this work was to analyze such effects. Animals (Wistar rats) exhibited three different behavioral and electrophysiological states of vigilance: wakefulness, slow wave sleep (SWS), and rapid eye movement (REM) sleep. Oral treatment with oxcarbazepine (100 mg/kg) produced an increment in total sleep time throughout the recording period. This increment involved both SWS and REM sleep. Mean duration of the REM sleep phase was not affected. In contrast, the frequency of this sleep phase increased significantly across the 10-hour period. REM sleep latency shortened significantly. Results obtained in this work indicate that oxcarbazepine's acute effects point to hypnotic properties.

Potential mechanisms of action of lamotrigine in the treatment of bipolar disorders

Based on the mood-stabilizing properties of carbamazepine and valproate, new anticonvulsants have been explored for use in bipolar disorders. One such agent, lamotrigine, has a novel clinical profile in that it may "stabilize mood from below," as it appears to maximally impact depressive symptoms in bipolar disorders. In this paper, we review the mechanisms of action of lamotrigine in an effort to understand the basis of its distinctive clinical use in the management of bipolar disorders as well as its diverse antiseizure effects. We consider lamotrigine mechanisms, emphasizing commonalities and dissociations among actions of lamotrigine, older mood stabilizers, and other anticonvulsants. Although ion channel effects, especially sodium channel blockade, may importantly contribute to antiseizure effects, such actions may be less central to lamotrigine thymoleptic effects. Antiglutamatergic and neuroprotective actions are important candidate mechanisms for lamotrigine psychotropic effects. Lamotrigine has a variable profile in kindling and contingent tolerance experiments and does not appear to have robust gamma-aminobutyric acid or monoaminergic actions. Lamotrigine intracellular signaling effects warrant investigation. Although lamotrigine mechanisms overlap those of other mood-stabilizing anticonvulsants, important dissociations suggest candidate mechanisms, which could contribute to lamotrigine's distinctive psychotropic profile.

Effect of antiepileptic drugs on sleep

The interactions between sleep and epilepsy are well known. A nodal point of the relationship between sleep and epilepsy is represented by pharmacological treatment. Sleep disturbances such as drowsiness are among the most frequent side effects of treatment with antiepileptic drugs, since they can deeply modify both sleep architecture and the sleep-wake cycle. Severe daytime somnolence affects patients' activities and it may facilitate the occurrence of seizures. These considerations underline the importance of antiepileptic drugs having anticonvulsant properties that do not negatively influence sleep and daytime somnolence. In this paper we review some relevant aspects of the effects of antiepileptic drugs on sleep.

Sleep dysfunction in Rett syndrome: a trial of exogenous melatonin treatment

Nine girls with Rett syndrome (mean age, 10.1 years) were monitored 24 hours a day over a period of 10 weeks using wrist actigraphy. Baseline sleep-wake patterns were assessed for 1 week. Subsequently, patients underwent a 4-week melatonin treatment period in a double-blind, placebo-controlled, crossover protocol that employed a 1-week washout between treatment trials. Melatonin doses ranged from 2.5 to 7.5 mg, based upon individual body weight. Baseline sleep quality was poor compared with healthy children. At baseline the group demonstrated a low sleep efficiency (mean [+/- SE], 68.0+/-3.9%), long sleep-onset latency (42.1+/-12.0 minutes), and a short and fragmented total sleep time (7.5+/-0.3 hours; 15+/-2 awakenings per night). Melatonin significantly decreased sleep-onset latency to (mean +/- SE) 19.1+/-5.3 minutes (P<0.05) during the first 3 weeks of treatment. While the variability of individual responsiveness was high, melatonin appeared to improve total sleep time and sleep efficiency in the patients with the worse baseline sleep quality. Finally, a 4-week administration of melatonin appears to be a safe treatment as no adverse side effects were detected, yet long-term effects of chronic melatonin use in pediatric patients are unknown at this time.