Levetiracetam administration

Pharmacokinetics Absorption is rapid, with peak plasma concentrations occurring in approximately 1 hour following oral administration in fasted subjects. Steady state is achieved after 2 days of multiple twice/day dosing. Levetiracetam is not extensively metabolized. The plasma half-life in adults is approximately 7 hours. Levetiracetam is eliminated from the systemic circulation by renal excretion. 

Renal function impairment Take caution in dosing patients with moderate and severe renal impairment and patients undergoing hemodialysis. Reduce dosage in patients with impaired renal function receiving levetiracetam, and give supplemental doses to patients after dialysis (see Actions and Administration and Dosage). 

Levetiracetam acts in a manner different to other antiepilepsy drugs. It has a potentially broad spectrum of use but is currently indicated for adjunctive treatment in partial seizures with or without secondary generalisation. It is rapidly and completely absorbed after oral administration, and is effective with twice-daily dosing. Its therapeutic index appears to be high and the commonest of the adverse effects are asthenia, dizziness and drowsiness. 

Levy RH, Ragueneau-Majlessi I, Baltes E. Repeated administration of the novel antiepileptic agent levetiracetam does not alter digoxin pharmacokinetics and pharmacodynamics in healthy volunteers. Epilepsy Res 2001 46(2) 93-9. 

Ragueneau-Majlessi I, Levy RH, Meyerhoff C. Lack of effect of repeated administration of levetiracetam on the pharmacodynamic and pharmacokinetic profiles of warfarin. Epilepsy Res 2001 47(l-2) 55-63. 

Toxicity effects known to be associated with levetiracetam use include decreased RBC count and hematocrit, decreased neutrophil count, somnolence, asthenia, and dizziness. These toxicities may be associated with blood concentrations in the therapeutic range. Co-administration of cimetidine wiU interfere with the test, producing artifactually increased measurements of levetiracetam. The laboratory can identify the presence of cimetidine, and laboratory reports wiU reflect cimetidine interference if it is detected. 

In a retrospective analysis of 118 intravenous infusions of levetiracetam in 15 children with epilepsy, most of whom were aged under 4 years, the following adverse effects were noted during the post-infusion period lethargy n = 2), agitation (1), irritability (1), mild tremors (1), and ataxia (1) no adverse effects required drug withdrawal [207. Three patients had reductions in white blood cell counts within the first 4 days after administration of the first dose of levetiracetam. 

In 12 adults with status epilepticus, intravenous levetiracetam 2500 mg was added as soon as possible to a standardized regimen of intravenous clonazepam and/or rectal diazepam as needed followed by phenytoin or valproic acid no serious adverse effects could be related directly to the administration of levetiracetam [208 ]. 

In a retrospective study of 32 patients who had been given intravenous levetiracetam for status epilepticus, there was arterial hypotension after intravenous levetiracetam in four patients during co administration of propofol and during rapid infusion of phenytoin in one patient [210 ]. There... 

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