Optimal Result: 0.06 - 0.66 mmol/mol creatinine.

It is a metabolite of phenylalanine and is excreted in the urine of patients suffering from diseases like phenylketonuria.

2-Hydroxyphenylacetic acid may be an indication of SIBO. It also becomes elevated with Giardia.

What does it mean if your 2-Hydroxyphenylacetic result is too high?

Elevated 2-hydroxyphenylacetic acid is associated with intestinal bacteria overgrowth.

Possible causes:

- Excessive phenylaline (dietary or PKU) or tyrosine

- Reduced oxygenation (Fe deficiency, anemia, pulmonary disorder)

- Low tetrahydrobiopterin (BH4) - an essential cofactor for phenylaline, tyrosine, tryptophan & nitric oxide

Additional investigations:

- Urinary Amino Acids

- Iron Studies

Treatment considerations:

- Rule out excessive phenylaline & or tyrosine

- Address oxygenation (correct anemia, pulmonary problems, cardiac insufficiency)

- Supplement vitamin C (increases BH4 levels in the body)

- 5-MTHF (from folic acid) may help nitric oxide production when BH4 is low

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