INTRAVENOUS ADMINISTRATION OF FOSPHENYTOIN - OPTIONS FOR THE MANAGEMENT OF SEIZURES

Fosphenytoin is a water-soluble disodium phosphate ester of phenytoin that is converted in plasma to phenytoin. Fosphenytoin is compatible w ith most common IV solutions and can be administered safely through th e IM route. An additional safety factor is the absence of propylene gl ycol in the fosphenytoin formulation. Propylene glycol is used as a ve hicle in the IV phenytoin preparation and by itself may produce seriou s cardiovascular complications. Studies of the pharmacokinetics, safet y, and tolerance of IV fosphenytoin have demonstrated that fosphenytoi n produces phenytoin plasma concentrations similar to those achieved w ith oral and IV phenytoin, but without significant cardiovascular effe cts and only minimal discomfort at the injection site. Aside from loca l reactions, the most common adverse events associated with fosphenyto in have been pruritus and reactions typical of phenytoin (e.g., dizzin ess, somnolence, and ataxia). Fosphenytoin represents a significant ad vance in the treatment of patients with seizures who require parentera l therapy.