What are the symptoms of PKU?
A. The symptoms of PKU are caused by high levels of Phe in the body. If untreated in childhood, these very high levels of Phe cause severe mental retardation. Even in babies and children who are treated, high levels of Phe may cause symptoms like being cranky or fretful, unable to focus, and anxious.16 In adults, when Phe levels are too high, problems can include:1,3,4,5 • Lower intelligence (IQ) • Bad moods, being cranky or irritable • Feeling “foggy” • Thinking and responding slower • Depression • Feeling anxious • Not being able to focus or pay attention When PKU is managed well and Phe levels stay low, people with PKU can expect to lead healthy and fulfilling lives. By keeping blood Phe levels low, excess Phe will not accumulate in the brain to cause problems.
