Phenylketonuria is the most frequent disturbance of amino acid metabolism. Untreated
patients present mental retardation whose pathophysiology is not completely established. In
this work we discuss the oxidative stress in phenylketonuric patients. Several studies have
shown reduction in antioxidant defenses, possibly due to dietary restriction of nutrients with
antioxidant properties and increase in oxidative damage to biomolecules, probably
secondary to increased formation of reactive species. Therefore, antioxidants could be …