5-Hydroxytryptamine Test: Reference Range

5-Hydroxytryptamine (5-HT) Test, also known as serotonin blood test, measures the level of serotonin in the blood to help detect the presence of a carcinoid tumor.

Reference Range:

50 to 200 ng/ml. (0.28 to 1.14 µmol/L)

Note: Some people who carry carcinoid tumors still have normal test results.

What Do the Abnormal Results Mean?

A significantly elevated level of serotonin may indicate the presence of a carcinoid tumor. To diagnose the condition, other tests must be taken.


Keywords: 5-Hydroxytryptamine, 5-HT, Serotonin

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