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hyperthyroidism
(hi″pәr-thi´roid-iz-әm)
excessive functional activity of the thyroid gland; see also thyrotoxicosis. It affects women far more frequently than men, with peak incidence between 30 and 50 years of age. Manifestations vary from
mild symptoms of weakness, insomnia, weight loss, and tremulousness to extreme tachycardia, palpitations, exertional dyspnea, and ankle edema. The hyperthyroid patient's metabolic rate is greatly accelerated, speeding up bodily processes. Severity
of symptoms is related to patient age, length of illness, and level of excess thyroid hormone in circulation. Hyperthyroidism
is commonly part of Graves disease, a syndrome that may include goiter and exophthalmos, and is also seen in association with thyroiditis, thyroid cancer, molar pregnancy, hyperemesis gravidarum, and toxic multinodular goiter. Several different physiologic mechanisms may cause increased hyperthyroidism: increased synthesis and secretion of thyroid
hormones, excessive release of the hormones, or ingestion of excessive amounts of the hormones. adj., hyperthy´roid., adj.
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