Symptoms usually come on gradually, over weeks or months. Therefore, you may have hypothyroidism for a long time, even years, before you realize you are ill. If you are an older adult, it may be even harder to recognize you are ill because instead of getting the typical symptoms of hypothyroidism, you may just gain weight or feel tired. Symptoms vary with the severity of the hypothyroidism and the length of time your body has lacked the proper amount of thyroid hormone.

Symptoms include:

  • Enlargement of the thyroid gland, called goiter (this is not always present)
  • Fullness in the neck
  • Difficulty swallowing; this can happen if the goiter is very large

Goiter (Enlargement of the Thyroid Gland)

© 2009 Nucleus Medical Art, Inc.

Later symptoms or signs include:

  • Fatigue
  • Weakness
  • Coarse, brittle hair and hair loss
  • Dry, scaly skin
  • Intolerance to cold temperatures
  • Weight gain (average 10 lb)—This may happen despite having a poor appetite.
  • Constipation
  • Achy feeling all over
  • Depression and irritability
  • Memory loss and personality change
  • Irregular or heavy menstrual periods
  • Orange palms and soles (hypercarotenemia)
  • Facial puffiness
  • Swolen feet or hands
  • Numbness and tingling of extremities
  • Infertility
  • Reduced sweating
  • Sleep apnea
  • Galactorrhea

Symptoms of severe or prolonged cases include:

  • Diffuse swelling of the skin and tissue around the eyes
  • Slow heart rate
  • Hypothermia (low body temperature)
  • Hoarseness
  • Shortness of breath during exertion or when lying flat
  • Lethargy and mental decline

You may have only one of these symptoms, but usually patients have a combination. Occasionally, patients with hypothyroidism have no symptoms at all, or the symptoms are so subtle they go unnoticed for a long period of time.