A functional insufficiency of the thyroid gland, resulting in deficiency of the thyroid hormone.

A variety of severe physiological problems accompany the reduction in thyroid function and the clinical features are dry skin, coarse hair, intolerance to cold, cognitive impairment, and slowing of the relaxation phase of deep tendon reflexes.

Clinical features include dry, waxy type of swelling with abnormal deposits of mucin in the skin and other tissues.

The skin becomes puffy around the eyes and on the cheeks and the face is dull and expressionless with thickened nose and lips.