In-depth

Prevention

Heat and exercise

Risk factors

Dehydration and youth sports

Symptoms

Headache

Most headaches aren't caused by a serious illness, but some could be a sign of a life-threatening condition.

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

Urinalysis

Urinalysis can be used to assess your overall health, detect a wide range of disorders, or monitor a medical condition or treatment.

X-ray

X-rays are a form of radiation that can make images of your bones and internal organs.

Jul. 12, 2014

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