| Indication |
Used as adjunctive therapy in the treatment of partial onset
seizures in adults and children 4 years of age and older with epilepsy. |
| Pharmacodynamics |
Not Available |
| Mechanism of action |
The precise mechanism(s) by which levetiracetam exerts its
antiepileptic effect is unknown. The antiepileptic activity of
levetiracetam was assessed in a number of animal models of epileptic
seizures. Levetiracetam did not inhibit single seizures induced by
maximal stimulation with electrical current or different
chemoconvulsants and showed only minimal activity in submaximal
stimulation and in threshold tests. Protection was observed, however,
against secondarily generalized activity from focal seizures induced by
pilocarpine and kainic acid, two chemoconvulsants that induce seizures
that mimic some features of human complex partial seizures with
secondary generalization. Levetiracetam also displayed inhibitory
properties in the kindling model in rats, another model of human complex
partial seizures, both during kindling development and in the fully
kindled state. The predictive value of these animal models for specific
types of human epilepsy is uncertain. Levetiracetam is thought to
stimulate synaptic vesicle protein 2A (SV2A), inhibiting
neurotransmitter release. |
| Absorption |
Rapidly and almost completely absorbed after oral administration
(99%). Peak plasma concentrations occurring in about an hour following
oral administration in fasted subjects. |
| Volume of distribution |
Not Available |
| Protein binding |
Very low (<10%) |
| Metabolism |
The major metabolic pathway of levetiracetam (24% of dose) is an
enzymatic hydrolysis of the acetamide group. No CYP450 metabolism
detected. |
| Route of elimination |
Sixty-six percent (66%) of the dose is renally excreted unchanged.
The metabolites have no known pharmacological activity and are renally
excreted. The mechanism of excretion is glomerular filtration with
subsequent partial tubular reabsorption. |
| Half life |
6-8 hours |
| Clearance |
|
| Toxicity |
Side effects include aggression, agitation, coma, drowsiness, reduced consciousness, slowed breathing |
