Fosphenytoin (Cerebyx) Drug for Epilepsy: Use, Side Effects, Interactions

Fosphenytoin
(Cerebyx, United States and Canada)

Use:

Fosphenytoin or Cerebyx is an anticonvulsant used in conditions like epilepsy.

How It Works:

Fosphenytoin or Cerebyx is a prodrug meaning that once in the body Fosphenytoin or Cerebyx is converted the active phenytoin. It is an new injectable version of phenytoin and is intended to replace intravenous phenytoin. Fosphenytoin or Cerebyx is water soluble, better tolerated, and provides more reliable absorption than the presently available injectable phenytoin.

Side Effects:

Fosphenytoin or Cerebyx causes a brief intense itching usually in the groin. This side effect may be a reaction to the phosphate. It is not an allergic reaction.
Fosphenytoin or Cerebyx has fewer local side effects than phenytoin injection. It can cause transient paraesthesia, drowsiness, and dizziness.

Cautions for People:

Fosphenytoin or Cerebyx is convenient, however it is expensive.

Drug Interactions:

Because Fosphenytoin or Cerebyx can cause drowsiness it will interact with any other drug that also causes drowsiness.

Further Reading:

Pharmacotherapy 1994;14:47
Drugs 1994;48:153
Neurology 1996;46(6Suppl1):S3,S24

Added to Virtual Drugstore November 1996.

The relevant product monographs must be regarded as the appropriate sources of prescribing information.