TSH

Alternative names:

thyroid stimulating hormone; thyrotropin

What the risks are:

• excessive bleeding
• fainting or feeling lightheaded
• hematoma (blood accumulating under the skin)
• infection (a slight risk any time the skin is broken)
• multiple punctures to locate veins

Special considerations:

Drugs that can increase TSH measurements include antithyroid medications, lithium, and potassium iodide.

Drugs that can decrease TSH measurements include aspirin, dopamine, heparin, and corticosteroids.

Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.