Final answer:
The usual treatment for individuals with phenylketonuria (PKU) is a strict dietary restriction of phenylalanine combined with ensuring adequate intake of tyrosine, and in some cases medication such as Kuvan. This approach helps to prevent the accumulation of toxic phenylalanine levels.
Step-by-step explanation:
The usual treatment for people born with phenylketonuria (PKU), a genetic disorder, involves a combination of dietary restrictions and nutritional adjustments. It is essential that individuals with PKU maintain a strict dietary restriction of phenylalanine to prevent toxic levels of this amino acid from accumulating in the body and causing damage to the central nervous system and brain.
Furthermore, because their bodies cannot adequately break down phenylalanine into tyrosine, individuals with PKU need to ensure they have adequate tyrosine in their diet, which becomes a conditionally essential amino acid for them. Some medication, such as Kuvan, may also be prescribed to those with some residual enzyme activity. Thus, the correct answer to the treatment for PKU would be: 3) Dietary restriction of phenylalanine combined with adequate tyrosine.
It is crucial to start this special diet as early as possible to reduce the severity of symptoms like intellectual disability, seizures, and neurological deficits. Foods high in phenylalanine, such as certain animal products, starches, and artificial sweeteners like aspartame, must be avoided or carefully managed under medical supervision.