Thyroid Gland

The thyroid gland is found in the neck, below the Adam’s apple and is responsible for producing actual thyroid hormone in two forms: Thyroxine (T4) and Triiodothyronine (T3)

Thyroid hormone (T3, T4) is production is stimulated by Thyroid-stimulating hormone (TSH)

Most common problems associated with this gland include

  • Overproduction of thyroid hormone (HYPERTHYROIDISM)
    • Symptoms
      • Heat intolerance, increased sweating, weight loss with increased appetite, anxiety, irritability, palpitations (heart racing), oligomenorrhea (abnormal menses), increased stool frequency, shortness of breath, fatigue, weakness, double vision, dry-irritated eyes, tremors, bulging eyes, warm/moist skin, hair loss, paralysis (mostly in Asian population)
    • Causes:
      • Grave’s disease (Autoimmune)
      • Toxic multinodular goiter or Toxic Adenoma
      • Postpartum (painless) thyroiditis
      • Subacute (infectious) thyroiditis
      • Iodine excess (medication, iodinated contrast)
      • Factitious (ingestion of thyroid hormone unknowingly in food products)
      • Ectopic thyroid tissue (struma ovarii)
      • Chorionic gonadotropin-induced (choriocarcinoma, hydatidiform mole)
      • TSH-secreting pituitary adenoma
    • Treatment (where clinically indicated):
      • Anti-thyroidal drugs (Methimazole “MMZ”, Propylthiouracil “PTU”)
      • Radioactive Iodine-131
      • Surgery
  • Underproduction of thyroid hormone (HYPOTHYROIDISM)
    • Symptoms
      • Cold intolerance, lethargy, fatigue, weight gain, dry skin, hair loss, constipation, muscle pain, arthritis (joint swelling), menorrhagia (abnormally heavy and prolonged menstrual bleeding), hoarseness, facial or eye puffiness, dizziness (bradycardia), poor memory (dementia), swelling (non pitting), carpal tunnel syndrome
    • Causes
      • Chronic lymphocytic (Hashimotos’) thyroiditis
      • Radioactive iodine treatment or external neck radiation; radiation exposure
      • Thyroidectomy
      • Transient (recovery from illness)
      • Drugs (used to treat Hyperthyroidism)
      • Severe iodine deficiency
      • Congenital hypothyroidism
      • Secondary (central) hypothyroidism from pituitary or hypothalamic disease
    • Treatment
      • Medications
        • Natural thyroid hormone (NP thyroid, Armour, etc)
        • Levothyroxine
        • Liothyronine
      • Drug effectiveness
        • Limited if also taken with calcium , iron , caffeine, cholestyramine, sucralfate, and aluminum hydroxide
        • Metabolized faster if taken with estrogen, rifampin, some anti-seizure drugs, and some anti-cancer drugs