By Mayo Clinic Staff

Shock is a condition brought on by a sudden drop in blood flow. As a result, the organs don't get enough oxygen. If shock isn't treated, it can lead to permanent organ damage or death. (1p1; 2p)

Shock may be caused by many conditions, including:

• Trauma or injury.
• Blood loss from an open wound or internal bleeding.
• Heatstroke.
• Not enough fluids, also called dehydration.
• Severe, widespread infection.
• Drug overdose.
• Severe burns.
• Allergic reactions.

Symptoms of shock vary. They may include:

• Cool, clammy skin.
• Pale or ashen skin.
• Blue or gray tinge to lips or fingernails.
• Rapid pulse.
• Rapid, shallow breathing.
• Upset stomach or vomiting.
• Enlarged pupils.
• Extreme weakness.
• Dizziness or fainting.
• Confused, anxious, restless or irritable.
• Unconscious.

Call 911 or your local emergency number if you think a person is in shock. Then take the following steps.

• If you suspect head, neck or back injury, do not move the person unless you need to move to safety or give CPR.
• Lay the person down. Prop up the legs slightly, unless it causes pain, injury or breathing trouble.
• Keep the person still and comfortable. Loosen tight clothing.
• Begin CPR if the person shows no signs of life, such as no breathing or heartbeat.
• Control any bleeding by putting pressure on the wound.
• Keep the person warm with a blanket or clothing. Be sure to cover the head, hands and feet.
• If the person is overheated, cut or rip open clothing.
• If the person is having a severe allergic reaction, use an epinephrine autoinjector, if available, by pressing it into the person's thigh.
• If the person vomits or is bleeding from the mouth — and no spinal injury is suspected — turn the person onto one side to prevent choking.
• Don't let the person eat or drink anything. This may cause vomiting or choking.

If you suspect a person is in shock, call 911 or your local emergency number.

Symptoms of shock vary depending on circumstances and may include:

• Cool, clammy skin.
• Pale or ashen skin.
• A gray or bluish tinge to lips or fingernails.
• Rapid pulse.
• Rapid breathing.
• Nausea or vomiting.
• Enlarged pupils.
• Weakness or fatigue.
• Dizziness or fainting.
• Changes in mental status or behavior, such as anxiousness or agitation.

After calling 911 or your local emergency number, take the following steps right away:

• Lay the person down and elevate the legs and feet slightly, unless you think this may cause pain or further injury.
• Keep the person still.
• Begin CPR if the person shows no signs of life, such as not breathing, coughing or moving.
• Loosen tight clothing and, if needed, cover the person with a blanket to prevent chilling.
• If the person vomits or is bleeding from the mouth, and no spinal injury is suspected, turn the person onto a side to prevent choking.

• Don't let the person eat or drink anything.
• Don't move the person unless it's needed.