Total Triiodothyronine (Total T3)

For children under 1 year, do not feed for 30-40 minutes before the test. Do not eat for 2-3 hours before the test; still (non-carbonated) water is allowed. Avoid steroid and thyroid hormones (as agreed with your doctor) for 48 hours before the test. Avoid physical and emotional stress for 24 hours before the test. Do not smoke for 3 hours before the test.