What does the Glutamate test measure?

Why is Glutamate measured?

Urine glutamate measurement in functional testing is used to infer excitatory–inhibitory neurotransmitter balance, but the disconnect between peripheral and central glutamate pools limits clinical interpretation. Elevated urine glutamate may reflect high dietary intake or altered amino-acid metabolism; low values may accompany nutritional deficiency or impaired synthesis.

Reference ranges

Standard reference

Laboratory-specific; typically 10–50 µg/g creatinine for random urine.

Functional medicine optimal

No evidence-based optimal range exists for neuropsychiatric interpretation; urinary glutamate is a peripheral metabolite and not a proxy for central excitatory signalling.

Units

µg/g creatinine, nmol/mmol creatinine, µg/24 hr, nmol/24 hr, ng/mg creatinine, μg/mg creatinine

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.