levetiracetam, status epilepticus
P Bhargava. Intravenous Levetiracetam in Refractory Status Epilepticus. The Internet Journal of Neurology. 2008 Volume 10 Number 2.
Refractory status epilepticus is defined as seizures, which last longer than 60 minutes despite treatment with a benzodiazepine and an adequate loading dose of intravenous antiepileptic drug. 1It has a high mortality and requires prompt management. Currently available drugs like midazolam, pentobarbitol and propofol can cause hypotension and respiratory depression. We present control of Refractory status in three critically ill patients using intravenous levetiracetam, which has a unique drug profile.
Refractory status epilepticus (RSE) is defined 1 as seizures, which last longer than 60 minutes despite treatment with a benzodiazepine and an adequate loading dose of intravenous antiepileptic drug. Mortality ranges from 32-77% 2 and is compounded by other co morbid conditions and multiple organ dysfunctions in patients in the intensive care unit. RSE may cause irreversible brain injury. 3 The presently recommended drugs are midazolam, pentobarbital and propofol; which may necessitate ionotropic and ventilatory support. 4 Thus arises the need for early control of RSE using safer drugs. Levetiracetam (LEV) has a unique profile in lacking drug interactions as well as significant metabolism in the body 5 and may be a good alternative to the recommended drugs .We present three cases of RSE where Levetiracetam, given intravenously has been successful in abating RSE.
There were no signs of meningitis; CT Scan of the head was normal. Serum electrolytes and blood gases were normal. Cause of seizure was most likely tissue hypoxia.
The pharmacokinetics of levetiracetam were described by Pastalos. 5 He reported a bioavailabilty of 95% after oral ingestion, no protein binding, no hepatic or renal metabolism (34% dose metabolized 66% excreted unmetabolised in urine; metabolism is by hydrolysis in blood). There was no auto induction and no evidence of accumulation on multiple dosing. Moreover no clinically relevant interactions with other AED's were identified .He recommended the pharmacokinetics of levetiracetam as highly favorable and usage simple and straightforward. The successful use of oral LEV for RSE has been reported. 6 Ramel etal have demonstrated the safety and tolerability of intravenous LEV even at doses higher than those proposed. 7 The first clinical experience for intravenous LEV for status epilepticus was reported by Moddel etal. 8
LEV merits larger trials for patients of refractory status epilepticus and can be of much help especially in critically ill patients in the Intensive care where multiple factors may be causative for the seizure a drug with the features of LEV is well suited. In our patients also this unique profile of LEV led to it being used successfully in both the patients
Levetiracetam, owing to minimal drug interactions, can be used to control refractory status epilepticus effectively, especially for patients in the ICU.