Phenytoin (Dilantin) should not be infused at a rate greater than 50 mg/minute, to a total of 20 mg/kg.
Caution is encouraged while infusing due to the risk of inducing hypotension and cardiac arrhythmias, making cardiac monitoring during infusion mandatory.
These adverse effects are partly related to the propylene glycol used to solubilize phenytoin.
Additionally, the risk of local pain and injury, such as venous thrombosis and the purple glove syndrome, increases with rapid infusion rates.
