Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:
-- The first section of this topic is shown below --
- Phenytoin follows zero-order pharmacokinetics:
- Small incremental increase in dose can result in a large increase in plasma concentration.
- Half-life in overdose prolonged; may be up to 70 hr
- Cardiovascular toxicity from IV administration likely due to the diluent propylene glycol
- Fosphenytoin, a prodrug for parenteral administration, is metabolized to phenytoin, its active moiety.
- Phenytoin intoxication results from acute, chronic, or acute-on-chronic administration.
- If the cause of the intoxication is unclear in a patient receiving chronic phenytoin therapy, consider that there may have been a:
- Change in the brand of phenytoin
- Change in dosage form
- Drug interaction
- Change in serum albumin