Fainting: Warning Signs, Causes and What to Do

What it is

Fainting is a temporary loss of consciousness. It usually happens when blood pressure drops suddenly, cutting blood flow to the brain. It's more common in older people.

Warning signs

• feeling dizzy, lightheaded or nauseous
• your vision "whiting out" or "blacking out"
• cold, clammy skin

Then you lose muscle control and may fall.

Common causes

• heat or dehydration
• emotional distress
• standing up too quickly
• certain medicines
• a drop in blood sugar
• heart problems

When someone faints

1. Make sure their airway is clear.
2. Check for breathing.
3. Keep them lying down for 10–15 minutes.

Afterward

Most people recover completely, and fainting is usually nothing to worry about — but it can be a sign of a serious problem. If you faint, see your health care provider to find out why.

Sources

Based on the MedlinePlus health topic "Fainting," National Library of Medicine; a work of the United States government in the public domain.