Carbon Monoxide Poisoning

Reviewed/Revised Dec 2023
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Carbon monoxide is a colorless, odorless, tasteless gas. It is produced from burning substances, including in car engines, heating systems, and fireplaces.

What is carbon monoxide poisoning?

Carbon monoxide poisoning is sickness from breathing in too much carbon monoxide. Carbon monoxide can hurt you because it prevents oxygen in your blood from reaching your cells.

People who breathe in too much carbon monoxide can die.

  • Symptoms include headache, feeling sick to your stomach, confusion, clumsiness (poor coordination), and tiredness

  • You may mistakenly think you have flu or another illness

  • Install carbon monoxide detectors in your home—they alert you if there is carbon monoxide in the air

If you think you may be breathing in carbon monoxide, move outside to fresh air right away, and call for emergency medical assistance (911 in most areas of the United States).

What causes carbon monoxide poisoning?

Carbon monoxide comes from burning substances. Anything that involves burning something can produce carbon monoxide: house fires, car engines, fireplaces, furnaces, gas heaters, kerosene heaters, and stoves. To prevent carbon monoxide poisoning, fumes must be vented (released outside) properly.

What are the symptoms of carbon monoxide poisoning?

The first symptoms are:

  • Headache or dizziness

  • Feeling sick to your stomach

  • Throwing up

  • Feeling tired or having trouble focusing

  • Poor coordination (clumsiness)

Later, or with more severe carbon monoxide poisoning, you may

  • Be confused

  • Be unconscious or unresponsive

  • Have seizures (when your body moves and jerks out of your control)

  • Have pain in your chest

  • Feel like you can’t breathe

  • Feel faint or weak

Severe poisoning can kill you.

How can doctors tell if I have carbon monoxide poisoning?

Doctors will take a sample of your blood to check for carbon monoxide.

How do doctors treat carbon monoxide poisoning?

Doctors will give you oxygen. The oxygen will help remove the carbon monoxide from your blood.

  • If you have mild poisoning, you may just need fresh air

  • If you have severe poisoning, you may need to breathe oxygen through a face mask

How can I prevent carbon monoxide poisoning?

  • Install a carbon monoxide detector in your home

  • Make sure all fireplaces, furnaces, and stoves are installed and vented properly

  • Don't turn on your car in a closed garage

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