The safety and efficacy of fosphenytoin for the treatment of status epilepticus.

Fosphenytoin, a water-soluble prodrug of the antiepileptic drug phenytoin, is entirely and rapidly converted to this antiepileptic drug. The mechanism of action of fosphenytoin is related to the blockade of voltage-operated sodium channels. It was developed in order to obtain a phenytoin-like drug with improved water solubility. Its maximal plasma concentration is achieved within 90-190 min following intramuscular administration with bioavailability being complete after intravenous injection. The main indications for fosphenytoin are the treatment of convulsive status epilepticus and the prevention/management of seizures during neurosurgery. Adverse effects of fosphenytoin may include: cardiovascular events (hypotension, arrhythmias), paresthesias or pruritus or some central events - somnolence, headache, dizziness, nystagmus and ataxia. The incidence of purple glove syndrome (edema, discoloration and pain distal to the site of intravenous administration) is less frequent than after phenytoin. Generally, the development of fosphenytoin aimed at avoiding complications associated with parenteral use of phenytoin.