Uncommon skin complication of phenytoin
Typically associated with IV infiltration of phenytoin, but poorly understood pathophysiology
Proposed mechanisms include:
Chemical irritation from added propylene glycol and sodium hydroxide
Vasoconstriction
Vasculitis
Microthrombus formation
Phenytoin leakage into soft tissue with subsequent edema
Generally develops within first 24 hours after infusion, resolves within days to weeks 
Chemical irritation from added propylene glycol and sodium hydroxide
Vasoconstriction
Vasculitis
Microthrombus formation
Phenytoin leakage into soft tissue with subsequent edema
Purple glove syndrome
Simple IV fluid extravasation
Rucksack paralysis
Arterial thrombosis
Irukandji syndrome
Compartment syndrome
Pancoast syndrome
Cellulitis