In-depth

Causes

Heart arrhythmias

Hyperthyroidism

Hyperthyroidism occurs when your thyroid gland produces too much of the hormone thyroxine — speeding up your metabolism and sometimes leading to serious complications.

Complications

Symptoms

Fatigue

Fatigue can signal many things. Here are some tips to help you decipher why you're wiped out and to regain your energy.

Tachycardia

Tachycardia, a rapid heart rate, is caused by an abnormality in your heart's electrical impulses. Tachycardia can cause serious complications, including sudden cardiac arrest.

Tests and diagnosis

MRI

MRI uses a magnetic field and radio waves to create detailed images of the organs and tissues within your body.

Treatments and drugs

Jul. 01, 2014

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