Phenylketonuria (commonly known as PKU) is an inherited disorder that increases the levels of a substance called phenylalanine in the blood. Phenylalanine is a building block of proteins (an amino acid) that is obtained through the diet. It is found in all proteins and in some artificial sweeteners. Without treatment for PKU, phenylalanine would build up in body, and the build up would cause damage to nervous system and brain. It occurs in approximately 1 in 10,000 babies born in the UK. The condition is diagnosed through the neonatal screening programme. It is a life-long condition and is incurable.

The main component of PKU treatment is eating a special diet that limits the  intake of foods containing phenylalanine (mainly proteins). This is to ensure that the body has adequate protein. PKU sufferers also need to consume PKU formula (protein substitute). This is a medical food that contains all the amino acids that their body needs except phenylalanine. PKU diet must be maintained throughout life to manage symptoms.

PKU sufferers need regular blood test to check their phenylalanine levels. For example our son who is 2 year old needs these blood tests once a week. Phenylalanine levels needs to be maintained within safe range. When it is outside of the safe range, dietician will suggest necessary changes to protein food intake.