Symptoms and Signs of Carbon Dioxide (CO2) Poisoning

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 9/24/2021

Doctor's Notes on Carbon Dioxide (CO2) Poisoning

Carbon dioxide poisoning (also called hypercapnia or hypercarbia) results from high levels of carbon dioxide in the blood. Carbon dioxide poisoning often occurs while scuba diving, from inadequate ventilation, inadequate breathing, a tight wetsuit, overexertion, regulator malfunction, deep diving, and contamination of the air supply with exhaled gases, which can cause a carbon dioxide buildup. Carbon dioxide levels in the blood may increase, causing shortness of breath and drowsiness, resulting in carbon dioxide toxicity.

Symptoms of carbon dioxide poisoning include

Symptoms of severe cases of carbon dioxide poisoning may include

What Is the Treatment for Carbon Dioxide Poisoning?

Carbon monoxide poisoning is a medical emergency. Call 9-1-1 immediately if you or your family have symptoms and suspect there is exposure to carbon monoxide. Immediately get everyone and your pets out of the area of exposure to the outdoors while awaiting medical help.

Most mild to moderate carbon monoxide exposures respond to oxygen therapy. Blood levels of carbon monoxide will be checked to tailor the treatment type and duration. If the carbon monoxide poisoning is severe, high-pressure oxygen or mechanical ventilation (ventilator) may be needed. Also in severe cases, hyperbaric oxygen treatment may be necessary.

Carbon monoxide exposures can be prevented with the following steps:

  • Have a working carbon dioxide detector in the home
    • Do not forget to change the batteries regularly as needed
  • Ensure proper ventilation guidelines are followed when operating engine-powered devices
  • Do not leave a car running in a closed garage
  • Do not operate propane stoves or lanterns or gas generators inside the home or closed workspaces

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.