Catecholamines, Fractionated (24-Hour Urine with C)

Norepinephrine is a hormone and neurotransmitter produced by the adrenal glands and nervous system that regulates heart rate, blood pressure, and stress response. A plasma norepinephrine test measures circulating levels of this compound. Elevated levels may indicate stress, hypertension, or certain tumors (pheochromocytoma), while low levels can suggest autonomic nervous system dysfunction. This test is often used to evaluate blood pressure abnormalities and suspected hormonal disorders.

Dopamine is a neurotransmitter and hormone involved in mood, motivation, and movement. A 24-hour urine dopamine test measures dopamine metabolites excreted over a full day. Elevated dopamine levels may indicate a pheochromocytoma (rare adrenal tumor), while low levels can suggest Parkinson's disease or other neurological conditions. This test helps diagnose hormonal and neurological disorders.

This test measures total catecholamines (epinephrine and norepinephrine) in urine collected over 24 hours. These stress hormones are produced by the adrenal glands and regulate blood pressure, heart rate, and metabolism. Elevated levels can indicate a pheochromocytoma (a rare adrenal tumor), neuroendocrine tumors, or severe stress. This test is ordered when symptoms suggest excess catecholamine production, including unexplained high blood pressure, headaches, excessive sweating, or heart palpitations.

This urine test measures epinephrine (adrenaline), a stress hormone produced by the adrenal glands. Epinephrine is released during 'fight or flight' responses, increasing heart rate and blood pressure. This test is primarily used to diagnose pheochromocytoma, a rare tumor of the adrenal glands that causes excessive epinephrine production, resulting in severe hypertension, sweating, and heart palpitations. Elevated urinary epinephrine warrants further investigation for adrenal disorders.