endocrine and metabolic disorders
Hyperthyroidism
Introduction
Hyperthyroidism is characterized by hypermetabolism and elevated serum levels of free thyroid hormones. Symptoms include palpitations, fatigue, weight loss, heat intolerance, anxiety, and tremor. Diagnosis is clinical and with thyroid function tests. Treatment depends on cause. (See also Overview of Thyroid Function .) Hyperthyroidism can be classified on the basis of thyroid radioactive iodine uptake and the presence or absence of circulating thyroid stimulators (see table). 