Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1209 page)

   Oat cell carcinoma of the lung

   Pancreatic islet tumor

   Thyroid medullary carcinoma

Decreased In

   Down syndrome

   Severe depression

   Parkinson disease

   Phenylketonuria (treated and untreated)

   Renal insufficiency

   Teratomas

   Limitations

   Blood serotonin is very unstable.

   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.