10. Tachycardia
Hyperthyroidism, in contrast to Hypothyroidism, represents marked hyperactivity of the thyroid gland and the subsequent overproduction of thyroid hormones. As such, whereas Hypothyroidism is characterized by a “slowing down” of the body’s metabolic processes, Hyperthyroidism results in a dramatic “speeding up” of the metabolism. One of the primary consequences of this effect is the appearance of tachycardia or a sudden rise in the heart’s cardiac frequency. In other words, patients with tachycardia report experiencing too-fast contraction of the heart’s ventricles and by having a resting heart rate that exceeds 100 beats per minute.