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Serotonin Level, Serum

Mnemonic:    [SEROTONIN]
Name:    Serotonin Level, Serum
Specimen:    1 mL serum from a Red SST or Red top tube. Patient Prep: Abstain from medications for 72 hours prior to collection.

Specimen Preparation: Allow sample to fully clot. Centrifuge the tube and place the serum in a separate, labeled transfer tube within one hour.

Note: Medications that may affect serotonin concentrations include lithium, MAO inhibitors, methyldopa, morphine, and reserpine. In general, foods that contain serotonin do not interfere significantly. Slight increases may be seen in acute intestinal obstruction, acute MI, cystic fibrosis, dumping syndromes, and nontropical sprue. Metastasizing abdominal carcinoid tumors often show serotonin concentrations greater than 400 ng/mL.
Minimum Spec:    0.6 mL
Transport Temp:    Critical Frozen sample. Freeze immediately and transport frozen.
Spec Stability:    Stable 24 hours refrigerated.
Ref Lab/Code:    ARUP 0080397
  Method:    High Performance Liquid Chromatography (HPLC)
Note:    In general, EDTA whole blood (as compared to serum) preserved with ascorbic acid will give values most representative of blood concentrations. Most (95 percent) of blood serotonin is found in platelets. Refer to Serotonin, Whole Blood (ARUP test code 0080395). This is not currently an orderable test in PathNet.
Processing Info:    Separate samples must be submitted when multiple tests are ordered.