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Carbon Monoxide Poisoning


Carbon monoxide (CO) poisoning is a life-threatening condition caused by exposure to high levels of CO. Your brain, organs, and tissues can be damaged from a lack of oxygen. You will need to watch for new signs and symptoms for several weeks or months after treatment.


Call your local emergency number (911 in the US) if:

  • You have chest pain or an irregular or fast heartbeat.
  • You or someone close to you has a seizure or is unconscious.
  • You have trouble breathing or are breathing faster than usual.
  • You feel like you are going to faint.
  • You feel weak, have trouble moving, or have severe muscle pain.
  • Your urine becomes dark or red.

Call your doctor if:

  • You feel dizzy.
  • You have a headache or start to vomit.
  • Your eyesight becomes blurred.
  • You have questions or concerns about your condition or care.

What to do if you think you or someone else was exposed to CO:

CO poisoning can seem like the flu. Anyone who may have been exposed to CO needs to be checked by a healthcare provider. The following are steps to take if you believe you or someone else is near a source of CO:

  • Move into fresh air. If safely possible, shut off the source of the CO. Wait for a professional to help you if you cannot do this safely.
  • Call 911. Explain when the exposure happened and how long you think it lasted.
  • Start CPR if needed and you are trained on how to do this. CPR may be needed if the person is not breathing.

Prevent CO poisoning:

  • Install a CO detector in every sleeping area in your home. Place it 5 feet above the floor and away from fireplaces or gas-burning equipment. Change the batteries twice each year.
  • Check your chimney, furnace, or wood stoves. Check for problems every year before you use them. Have your fireplace flue cleaned on a regular basis.
  • Be careful with gas appliances. Do not use barbecues or heaters that burn fuel inside your home or other closed spaces. Do not use your gas kitchen oven to heat your home. Make sure appliances are properly hooded or vented.
  • Do not let motor vehicles run in closed areas. This includes letting your car run in a garage. If the car is outside, check that the exhaust pipe is not blocked.
  • Do not smoke. Cigarette smoke contains small amounts of CO. This increases your risk of CO poisoning if you are exposed to a source of CO. Ask your healthcare provider for information if you need help quitting.

Follow up with your healthcare provider as directed:

You may need to return to have more tests. Write down your questions so you remember to ask them during your visits.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Learn more about Carbon Monoxide Poisoning (Aftercare Instructions)

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