Serotonin, Serum

Serotonin, 5-Hydroxytryptamine

Test Codes

EPIC: LAB1232011, Beaker: Serotonin, Quest: 29851

Department

Send Outs

Instructions

This assay is NOT a Serotonin Release Assay (used for the diagnosis of heparin-induced thrombocytopenia).

Specimen Collection Criteria

Collect (preferred specimen): One plain Red-top tube.

Also acceptable: One Gold-top SST tube.

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to plastic transport tube and freeze (-20°C/-4°F or below) prior to transport.

Preparation for Courier Transport

Transport: 2.0 mL serum, frozen (-20°C/-4°F or below). (Minimum: 1.0 mL)

Rejection Criteria

Specimens not collected or processed as indicated.

In-Lab Processing

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to plastic transport tube and freeze (-20°C/-4°F or below).

Transport: 2.0 mL serum, frozen (-20°C/-4°F or below). (Minimum: 1.0 mL)

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): Unacceptable
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): 42 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.

Laboratory

Sent to Quest Diagnostics, Wood Dale, IL.

Performed

Monday – Saturday.
Results available in 3-5 days.

Reference Range

56-244 ng/mL

Test Methodology

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Interpretation

By report.

Clinical Utility

Serotonin, Serum – Serotonin concentrations are greatly increased in patients with carcinoid syndrome. Carcinoid tumors are associated with Multiple Endocrine Neoplasia (MEN) Types I and II. These tumors are associated with flushing, diarrhea, pain, and other symptoms.

CPT Codes

84260

Contacts

Last Updated

12/19/2025