The total thyroxine test measures the amount of thyroxine (T4) in your blood. Thyroxine is a hormone produced by your thyroid gland that helps regulate your metabolism. This test can help your doctor determine if your thyroid is functioning properly.

T4 (Total Thyroxine) is a key thyroid hormone that plays a critical role in regulating metabolism and bodily functions.

Key Characteristics: • Hormone produced by thyroid gland • Regulates metabolism, digestion, muscle function, and bone health • Produced with interaction between thyroid and pituitary glands

Normal Range: • Adults: 5.0 to 12.0 μg/dL • Specific ranges: • 4.5 – 10.9 mcg/dL • 5.4 to 11.5 mcg/dL

Clinical Significance: • Helps diagnose thyroid disorders • Indicates potential: • Hyperthyroidism (elevated levels) • Hypothyroidism (low levels)

Important Considerations: • Levels can be affected by: • Pregnancy • Estrogen medications • Anabolic steroids • Protein-binding abnormalities

The Total T4 test provides healthcare providers with a comprehensive assessment of thyroid hormone levels and potential metabolic dysfunction.