How Carbon Monoxide Poisoning Is Treated

Traditional and New Treatments for Carbon Monoxide Poisoning

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Oxygen therapy is the main treatment for carbon monoxide poisoning. That's because when you breathe carbon monoxide, it binds with and blocks hemoglobin, a protein in your blood that carries oxygen throughout your body. This starves your body of oxygen.

It doesn't take much carbon monoxide in the air you breathe to get carbon monoxide poisoning. However, it takes a lot of oxygen to get rid of it.

This article discusses the emergency treatment needed for carbon monoxide poisoning. This includes first aid steps, oxygen therapy at the hospital, and other treatment for complications.

What Is Carbon Monoxide Poisoning?
Verywell / Emily Roberts

First Aid Treatment

Carbon monoxide poisoning is a life-threatening emergency. If you suspect that someone has signs of carbon monoxide poisoning, get them outside into fresh air immediately. Call 911 or Poison Control at 1-800-222-1222.

Symptoms of carbon monoxide poisoning may include headache, fatigue, nausea, chest pain, shortness of breath, dizziness, confusion, irregular heartbeats, or blurry vision.

If you can quickly and safely do so, turn off the source of carbon monoxide.

If the person is unresponsive and isn't breathing, start CPR right away. Continue until they breathe on their own, someone else can take over CPR, or paramedics arrive. If you're alone with the person, do CPR for two minutes and then call 911.

Oxygen Therapy

If you're brought to the hospital with carbon monoxide poisoning, you'll spend several hours in the emergency department breathing pure oxygen.

Treating carbon monoxide poisoning requires, at a minimum, breathing 100% oxygen concentration for several hours to rid the bloodstream of carbon monoxide.

Always call 911 without delay if you suspect you or someone else has carbon monoxide poisoning.

Traditional Oxygen Therapy

The basic treatment for carbon monoxide poisoning is to administer high-flow oxygen using a non-rebreather mask. This is a face mask with a plastic bag hanging off it connected to a supply of high-concentration oxygen. A one-way valve keeps the air you exhale out of the bag.

You'll wear the mask as long as it takes to replace the carbon monoxide in your blood with oxygen. Oxygen therapy allows your body to get rid of carbon monoxide faster than just breathing the air around you.

For instance, if you receive 100% oxygen, the elimination half-life of carbon monoxide in your blood would take 74 minutes. Half-life is a measurement of the time it takes to eliminate half of a substance in the body. For complete elimination of the carbon monoxide, it would take 370 minutes —about six hours.

In contrast, the half-life of carbon monoxide without using oxygen is 320 minutes—more than five hours to reduce levels by half. At that rate, it would take about a day for the carbon monoxide to be completely removed.

Hyperbaric Oxygen Therapy

Another option is to administer oxygen under pressure in a hyperbaric chamber. You lie in the chamber and breathe 100% oxygen at a pressure that's about two times higher than normal atmospheric pressure.

In a hyperbaric chamber, oxygen therapy can reduce the elimination half-life of carbon monoxide to about 20 minutes.

What to know about treating carbon monoxide poisoning.

Verywell / Alex Dos Diaz

Unfortunately, hyperbaric chambers are not always readily available, especially in rural areas. Even in areas that have access to hyperbaric oxygen therapy, it can take a couple of hours to arrange the treatment.

Considering the patient will receive traditional oxygen administration during the waiting period, the benefit of a slightly faster treatment might already be lost. Plus, if multiple patients are affected by carbon monoxide exposure, only one at a time can be treated in the hyperbaric chamber.

There is clear evidence that hyperbaric oxygen therapy clears carbon monoxide from the blood faster. However, evidence is conflicting on whether patients are better off because of it.

One analysis of randomized trials found mixed results looking at the neurological outcomes of carbon monoxide patients receiving hyperbaric oxygen therapy.

Another review of studies showed that hyperbaric oxygen therapy could be more effective than traditional oxygen therapy. It had greater advantages for those with life-threatening carbon monoxide levels or with neurological symptoms.

However, the review noted that traditional oxygen therapy was a reasonable alternative because of its cost-effectiveness and widespread availability.

Hyperbaric therapy could possibly be helpful, especially in cases of severe poisoning, but there's no reason to fret if it isn't readily available.

Other Emergency Treatments

Providing oxygen to reduce the levels of carbon monoxide in the bloodstream is just one part of treatment. Damage to the brain and heart from a lack of oxygen in the blood during carbon monoxide poisoning requires treatment as well.

Depending on the severity of the poisoning, patients could need support for brain and cardiac function. Some patients will need treatment for brain swelling, which could include medications and admission to the intensive care unit.

The heart is sensitive to a lack of oxygen. Patients could experience cardiac arrhythmias (irregular heartbeats), which could be treated in the hospital with medication or electrical therapy.

High levels of free oxygen in the bloodstream—oxygen molecules that are not bound to hemoglobin, also known as free radicals—can also increase inflammation. This adds to the potential need for cardiac intervention.


Oxygen therapy is a life-saving treatment for carbon monoxide poisoning. That's because carbon monoxide gets in your blood and starves your body of oxygen. To get rid of it, you'll need to receive a high concentration of oxygen.

For signs or symptoms of carbon monoxide poisoning, call 911 immediately. Get outside in the fresh air to get away from the source of carbon monoxide. Start CPR if you're with someone who isn't breathing.

At the hospital, you'll likely receive a high concentration of oxygen through a non-rebreather mask. Hyperbaric chambers can administer oxygen at higher levels of pressure. For damage to your brain or heart from oxygen loss, you may need other therapy, including medication or intensive care.

A Word From Verywell

With carbon monoxide poisoning, getting emergency care is essential. Healthcare providers can make sure you get a high concentration of oxygen to rid your blood of any carbon monoxide. Getting this oxygen quickly can help prevent permanent damage or even death.

Frequently Asked Questions

  • Is there a way to get carbon monoxide out of the body?

    The most effective way to rid someone's body of carbon monoxide is to give them 100% oxygen as soon as they've been diagnosed with CO poisoning.

    This can be done via one of several methods: continuous airway pressure (CPAP), an oxygen mask with a valve, or administration of oxygen through a reservoir mask at a rate of 15 liters per minute.

    This helps to force the CO out so it can be replaced with oxygen.

  • How long does it take to rid the body of carbon monoxide?

    It takes four and a half to five hours for the amount of CO in the body to naturally reduce by half while breathing regular air, about an hour and a half with treatment with 100% oxygen, and 20 minutes with 3 atmospheres of pressure in a hyperbaric chamber.

    Oxygen treatment should be continued until blood levels of carboxyhemoglobin (COHb), which is formed when CO bonds with red blood cells, drops to less than 3% and symptoms have abated.

  • What happens if carbon monoxide poisoning isn't treated?

    The potential damage caused by carbon monoxide (CO) is cumulative, so any symptoms or complications of exposure will depend on how much CO is in the blood and how long it's been there.

    Brief exposure to a small amount of CO may cause nausea and headache, while lengthy exposure to a large amount of CO can lead to considerably more serious problems.

    This includes shortness of breath (dyspnea), changes in mental alertness, neurological problems, coma, and death.

  • Is carbon monoxide poisoning always fatal?

    No, but it can cause permanent damage if it isn't detected and treated promptly.

    When carbon monoxide attaches to hemoglobin, it's called carboxyhemoglobin (COHb). Blood levels of COHb that reach 60% or more can bring on death quickly. And when CO poisoning damages the heart, it can increase the risk of death over the next 10 years.

    Even if CO poisoning isn't fatal, it can cause symptoms days or weeks after exposure such as vision problems, abdominal pain, and neurologic deficits.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Rod Brouhard, EMT-P
Rod Brouhard is an emergency medical technician paramedic (EMT-P), journalist, educator, and advocate for emergency medical service providers and patients.