FOSPHENYTOIN (CEREBYX)

Fosphenytoin is a phosphate ester prodrug of phenytoin developed as a replacement for standard injectable sodium phenytoin. After absorption , phenytoin is cleaved (conversion half-life 8-15 min) from fosphenyto in. Unlike phenytoin, fosphenytoin is freely soluble in aqueous soluti ons (including standard intravenous solutions) and rapidly absorbed by the intramuscular route. Fosphenytoin has been tested successfully fo r three indications in humans: intramuscular maintenance dosing, intra muscular loading dose administration, and intravenous treatment of sta tus epilepticus. Local toxicity (pain, burning, itching) is less by th e intramuscular or intravenous route for fosphenytoin than for standar d injectable sodium phenytoin. Systemic toxicity is similar with both preparations except that hypotension is less common and paresthesias a re more common with fosphenytoin.