Potential problems

Anorexia – Refusal to eat

Infants and/or little children can reject food at certain times without being ill:

  • if he or she refuses to eat, do not get anxious and do not try to get your child to eat for an hour or more, and do not reheat the plate or resort to “tricks” to get your child to eat: TV, games, bringing in different people, forcing, etc. You should rather take the plate away and refrain from bringing dessert. That way, your child will be hungry and more open to eating at the next meal. If your child sees you anxious, this attitude may become more common:
  • if he or she will not eat vegetables, do not give in by giving him or her other low protein foods instead. Do not take the easy way out by including chips with each meal. They can only be eaten in “restricted” amounts.
  • do not give your child small amounts of forbidden foods to get him or her to eat or to make him or her happy: your child cannot understand that some things are partly allowed or that a food that is allowed today is forbidden tomorrow.


Mom and Dad need to be on the same page on this because, if your child sees you react differently, anorexia and/or refusal to eat may become entrenched. Talk with your dietitian to make sure that you are giving your child the right amount of the mixture of amino acids. An excessive amount may curb your child’s appetite.

If your child has a small appetite, your dietitian will look at the possibility of choosing a mixture with fewer calories with you.


Refusal to take amino acids mixes

Your child may refuse to take the mixture of amino acids. This may be due to the preparation method:

  • if the mixture is too diluted, the volume may be excessive,
  • whereas if it is too thick, it may be too concentrated.


It may be due to an irregular schedule. Your child must understand that the mixture is essential to his or her well-being and that it is part and parcel of his or her diet.

It must be taken every day. It is your responsibility. It can happen if the child sees the parents concerned about it, because they know it is important. If the situation is too difficult, ask a psychologist for help; he or she will provide reassurance.

If the child refuses to eat fruits and vegetables or take the mixture of amino acids, do not give in —there are no immediate signs of intoxication. However, failing to strictly follow the diet, with diverging attitudes, will slowly but steadily lead to toxicity and increased blood concentrations, with the resulting health problems.


Intercurrent diseases

Even mild diseases can cause fever. Little children with a fever often lose their appetite. Do not worry if your child does not eat all the parts. Do not force him or her to eat. Give your child sweet, easy to eat foods with lots of calories: compote, fruit juices or fizzy drinks, special hypoproteic foods, desserts or fruits mixed with a hypoproteic drink, hypoproteic biscuits crushed and mixed with a hypoproteic drink, etc.

Try giving the mixture of amino acids in small doses spread throughout the day. Although fever increases the blood concentration of phenylalanine, there is no reason for concern in the short term.


Vomiting – diarrhoea

See your doctor to find the cause. He or she will treat your child like any other child with vomiting and/or diarrhoea. Just one word of caution: do not use “antidiarrhoeal milk”, which tends to contain plenty of protein and, therefore, phenylalanine.

Do not worry. Any increase in the blood concentration will be short-lived and devoid of any effect on the prognosis of your child.