Q: 42 year old male in ICU went into grand mal seizure. 2 mg of IV lorazepam is administrated but did not bring any relief. Another dose of 2 mg of lorazepam is ordered and simultaneously phenytoin is ordered. Which one caution should be exercise very closely while treating this patient?
Answer: Phenytoin is incompatible with almost any of the benzodiazepines, and should not be administrated with same IV line, otherwise will precipitate. Another IV line should be established ASAP. Similarly is true for phenytoin and any fluid with glucose/dextrose. This does not apply to fosphenytoin infusion.