Seratonin levels

Im going through some health problems right now.  Ive had 1 doctor tell me that I have an anxiety disorder that is causing all the tingling, burning, and muscle cramping in my body.  He tried me on elavil which greatly increased my heart rate.  Ive been on Ativan which has been "ok", but not a real big help.  My question is,  how can one be certain that a person has an anxiety or depression disorder?  How are seratonin levels measured in the body?  Thank you

[HFHS.MD-AJ]

NL,

With the limited information provided, it would be impossible for me to give you a diagnosis. Your symptoms of tingling, burning and mucle cramping should be evaluated by your primary care physician, to rule out medical/neurological causes. If no medical/neurological causes are found, your symptoms may be due to an anxiety or somatoform disorder, in which case you may find consultation with a mental health professional helpful. Serotonin levels in the body are usually measured indirectly, by obtaining levels of a serotonin metabolite (5-Hydroxyindoleacetic acid, 5-HIAA) in urine or cerebrospinal fluid samples. It is not standard clinical practice to measure serotonin levels, except in research settings. Please refer to our forum archives for more information on anxiety and depression, and discuss your concerns further with your treating physician.