Thyroid Stimulating Hormone (TSH) with 24-Hour Urine Free Cortisol and Plasma Cortisol

Why This Test Is Done

Your doctor may order this test if you have symptoms like fatigue, weight changes, mood swings, or unexplained stress. It can also be used to monitor conditions like hypothyroidism, hyperthyroidism, or Cushing’s syndrome. Some people get it as part of a routine check-up or before starting certain medications.

What to Expect Before the Test

For the TSH blood test, you’ll typically have a simple blood draw. For the 24-hour urine cortisol test, collect all urine for a full day (usually starting after morning pee). Drink plenty of water but avoid caffeine or alcohol for 24 hours before collecting. Cortisol tests may require fasting, so follow your doctor’s instructions.

What the Results Mean

TSH measures how well your thyroid gland is working. High or low TSH can signal thyroid problems. Cortisol in blood and urine helps check adrenal function—elevated levels may indicate Cushing’s syndrome, while low levels could suggest adrenal insufficiency. Your doctor will interpret results in the context of your symptoms and medical history.

Common Conditions This Test Helps Diagnose

This test can help diagnose or monitor conditions like hypothyroidism (low thyroid hormone), hyperthyroidism (overactive thyroid), adrenal disorders (e.g., Addison’s disease), or Cushing’s syndrome (high cortisol). It may also be used to evaluate pituitary function or rule out stress-related hormone imbalances.