TSH

You should get a TSH test if you have symptoms of hypothyroidism, such as fatigue, weight gain, hair loss, or cold intolerance, or of hyperthyroidism, such as weight loss, palpitations, or anxiety. It is also recommended during pregnancy, for infertility or irregular periods, for routine health check-ups, and for monitoring thyroid medication.

No special preparation or fasting is required for a TSH test. Give your sample in the morning, when TSH levels are more consistent, and take your thyroid medicine after the sample unless your doctor advises otherwise. Stop biotin supplements 48–72 hours before the test, and inform your doctor about pregnancy or other medications.

No, fasting is not required for a TSH test. You can eat and drink normally before giving your sample. A morning sample is preferred, and you should take your thyroid medicine after the test unless your doctor advises otherwise. Stop biotin supplements 48–72 hours beforehand, as biotin can affect results.