title: Intramuscular fosphenytoin (Cerebyx) in patients requiring a loading dose of phenytoin.
abstract: Fosphenytoin (Cerebyx), is a water soluble prodrug that is rapidly and completely converted to phenytoin. This study reports the injection-site tolerance and safety of intramuscular fosphenytoin (> 10 mg/kg doses) in 60 patients requiring a phenytoin loading dose. Patients received injections at single or multiple sites with volumes ranging from 4 to 30 ml per injection site. The majority of patients had no irritation (erythema, swelling, tenderness, bruising) or complaints of discomfort related to fosphenytoin injection either after injection (95%) or at follow-up (88%). Irritation, when reported, was mild in all cases. Forty of 60 patients (67%) reported transient side effects, primarily involving the central nervous system, such as nystagmus, dizziness or ataxia, which are commonly associated with phenytoin therapy. All patients received prescribed doses; no patient had an injection(s) stopped due to intolerance or side effects. No serious adverse events occurred with intramuscular fosphenytoin. In this study, intramuscular fosphenytoin was demonstrated to be a safe and well tolerated, and in many instances, a preferable alternative to other means of phenytoin loading.
authors.affiliation: International Center for Epilepsy, University of Miami, FL 33136, USA.
authors.forename: R E
authors.initials: RE
authors.lastname: Ramsay
authors.forename: B J
authors.initials: BJ
authors.lastname: Wilder
authors.forename: B M
authors.initials: BM
authors.lastname: Uthman
authors.forename: W R
authors.initials: WR
authors.lastname: Garnett
authors.forename: J M
authors.initials: JM
authors.lastname: Pellock
authors.forename: G L
authors.initials: GL
authors.lastname: Barkley
authors.forename: I E
authors.initials: IE
authors.lastname: Leppik
authors.forename: L E
authors.initials: LE
authors.lastname: Knapp
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000927:Anticonvulsants / Q000009:adverse effects / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005500:Follow-Up Studies; D006801:Humans; D007273:Injections, Intramuscular; D008875:Middle Aged; D010672:Phenytoin / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D011355:Prodrugs / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000927:Anticonvulsants; D011355:Prodrugs; D010672:Phenytoin; C043114:fosphenytoin