All ZeroTP products are concentrated, mostly highly concentrated mixtures of highly purified L-amino acids free of tyrosine and phenylalanine (TP). ZeroTP products are balanced diets for dietary management of tyrosinemia or alkaptonuria - enriched with vitamins, minerals and trace elements. There are several products for each age group, which differ in properties such as the form of administration. They can be very easily substituted for one another or combined with each other throughout the day.