This Dr. Axe content is medically reviewed or fact checked to ensure factually accurate information.
With strict editorial sourcing guidelines, we only link to academic research institutions, reputable media sites and, when research is available, medically peer-reviewed studies. Note that the numbers in parentheses (1, 2, etc.) are clickable links to these studies.
The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.
This article is based on scientific evidence, written by experts and fact checked by our trained editorial staff. Note that the numbers in parentheses (1, 2, etc.) are clickable links to medically peer-reviewed studies.
Our team includes licensed nutritionists and dietitians, certified health education specialists, as well as certified strength and conditioning specialists, personal trainers and corrective exercise specialists. Our team aims to be not only thorough with its research, but also objective and unbiased.
The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.
Carbon Monoxide Poisoning Symptoms + 5 Safety Tips to Prevent CO Poisoning
April 23, 2018
If you’re reading this sentence right now and think you may be experiencing carbon monoxide poisoning symptoms, please step outside into fresh air and seek emergency medical care right now! You absolutely do not want to go back into your home until you’re sure it’s safe.
Every year, over 20,000 people in the United States go to the emergency room for unintentional carbon monoxide poisoning not linked to fires. Of those 20,000, more than 4,000 are hospitalized and more than 400 people die. (1) It’s very frightening yet factual that death can result from just a few minutes of exposure to higher levels of carbon monoxide in the air or from only an hour of exposure to lower levels. (2)
What do you do if your carbon monoxide detector goes off? How long does it take to get carbon monoxide out of the body? I’m about to discuss the answers to these questions as well as the best ways to prevent carbon monoxide poisoning in the first place.
What Is Carbon Monoxide Poisoning?
Before we get to what is carbon monoxide poisoning, let’s first answer the following question: What is carbon monoxide? Carbon monoxide is a tasteless, colorless, odorless gas and a scary source of indoor air pollution. It is often referred to as the “invisible killer.” This gas is produced by burning gas, wood, propane, charcoal or other fuel. Whenever fuel is burned in an automobile, heater, fireplace, grills, gas ranges, stoves, lanterns or furnaces.
What types of situations can lead to a dangerous accumulation of CO gas indoors? If an appliance or engine is not properly ventilated and is in a tightly sealed or enclosed space then there is strong potential for carbon monoxide to reach unsafe amounts in the air. You can experience carbon monoxide symptoms in house situations (a “house” includes apartments, mobile homes or any other structure in which someone lives). There is also the possibility of carbon monoxide poisoning car related incidents, which typically occur in a garage.
It’s scary but very true that it only takes a few minutes of high carbon monoxide exposure to induce major organ damage or even death. Carbon monoxide poisoning occurs in a person or pet when carbon monoxide builds up in the bloodstream leading to deprivation of oxygen to vital organs like the heart and brain.
Red blood cells normally transport oxygen from the lungs to the cells of our bodies. When CO poisoning occurs, carbon monoxide is inhaled, passes from the lungs to the blood stream, and then the carbon monoxide attaches to the red blood cells, displacing oxygen from the bloodstream. Since oxygen cannot be transported by hemoglobin that already has carbon monoxide attached to it, as exposure to CO continues, the body is being robbed of oxygen more and more. The carbon monoxide can also mix with bodily proteins leading to tissue damage.
How long does it take to get carbon monoxide poisoning? It can take anywhere from minutes to hours depending on the levels of carbon monoxide. With high levels, it can only take a couple of minutes before major injury or even death occurs. (3)
Signs and Symptoms
How do you know if you have carbon monoxide poisoning? What does it feel like to have carbon monoxide poisoning?
Carbon monoxide poisoning symptoms that may occur from breathing low levels of CO include: (4)
- Headache
- Nausea
- Dizziness
- Weakness
- Confusion
- Disorientation
Breathing in high levels can cause the following carbon monoxide poisoning symptoms:
- Sleepiness
- Confusion
- Nausea
- Anxiety or depression
- Vomiting
- Impaired vision
- Impaired coordination
- Disorientation
These are common symptoms of carbon monoxide poisoning in adults and children. With pets, it’s unclear if they experience headaches as one of the early signs of carbon monoxide poisoning. If your dog or cat is acting confused, lethargic or is having trouble breathing, these can be signs of poisoning.
Sometimes carbon monoxide poisoning happens quickly, but other times the poisoning is slow and can occur over the span of weeks or even months when the CO exposure is at low levels. When poisoning is slow like this, carbon monoxide poisoning symptoms can be similar to flu symptoms and include fatigue, headache, nausea and vomiting. Lengthy exposure to CO at low levels can also lead to physical CO gas leak symptoms including memory issues, numbness, vision disturbances and poor sleep. (2)
Causes and Risk Factors
There are several possible carbon monoxide poisoning causes. The following items are examples of potential causes of CO poisoning if you inhale too much CO from them: (5)
- Fireplace
- Fuel-burning space heater
- Furnace
- Gas stove or stovetop
- Generator
- Idling car or truck in a garage or enclosed space
- Recreational vehicles with gas heaters
- Water heater
According to the Centers for Disease Control and Protection (CDC), anyone and everyone is at risk for CO poisoning. They say that infants, the elderly, people with chronic heart disease, anemia, or breathing problems are more likely to get sick from CO. (1)
Exposure to carbon monoxide can be particularly dangerous for the following people: (7, 8, 10)
Unborn babies: Unborn babies are at greater risk for harm due to CO poisoning because fetal blood cells are known to take up carbon monoxide more readily than adult blood cells. To be more specific, carbon monoxide is said to attach to fetal hemoglobin at a level 10 percent to 15 percent higher than in the mother.
Children: Young children take breaths more often than the average adult, which may increase their risk of carbon monoxide poisoning. Due to their smaller size and the fact that they are still growing and developing, they are also believed to be at greater risk for damage including developmental disorders.
Anemia: People with anemia have a reduced number of healthy red blood cells, which puts them at even greater risk for negative effects of CO poisoning since the carbon monoxide has such a direct effect on red blood cells of the body robbing them of oxygen.
Chronic heart disease: Since carbon monoxide poisoning is known to affect the heart in particular, people with an already weakened heart, such as those with coronary heart disease, are at greater risk for harm from CO poisoning.
Breathing problems: Carbon monoxide is a known trigger for those with respiratory issues such as people with asthma.
Elderly: Older people may be more likely to develop brain damage from CO poisoning. In addition, people over the age of 65 are more likely to have a respiratory or heart condition that can predispose them to a more severe case of CO poisoning.
Carbon monoxide poisoning can be especially dangerous or deadly for people who are asleep or intoxicated due to alcohol and/or drug use. These two categories of potential CO poisoning victims are more likely to experience irreversible brain damage or even be killed by CO before anyone even knows there’s a serious issue at hand. (8)
Diagnosis
To confirm whether or not someone has carbon monoxide poisoning, a blood test is performed to look at the levels of oxygen and carboxyhemoglobin (carbon monoxide attached to hemoglobin). More tests may be required if potential carbon monoxide poisoning symptoms warrant them or if the individual is pregnant. A pregnant woman may require fetal monitoring. Other tests can include an electrocardiogram (ECG), a magnetic resonance imaging (MRI) or computed tomography (CT) scan of the brain.
Conventional Treatment
Depending upon the length and degree of exposure, complications of carbon monoxide poisoning include permanent brain damage, heart damage — which can lead to life-threatening cardiac complications — or death.
So there is no question about it, if you think you’re experiencing carbon monoxide poisoning symptoms, you need to get out of the area you’re in, get fresh air outdoors and call 911 once you’re outside. There should be no delay in getting outdoors, so call once you are outside.
At the hospital, carbon monoxide poisoning treatment is likely to include breathing in pure oxygen through a mask placed over your nose and mouth. If you are unable to breathe independently, a ventilator may be used.
In some cases, especially severe ones, of carbon monoxide poisoning symptoms, hyperbaric oxygen therapy is a recommended form of treatment. This oxygen therapy is known for helping to protect heart and brain tissue from major damage. Hyperbaric oxygen is often recommended for pregnant women because unborn children are more susceptible to damage from carbon monoxide poisoning.
How long does carbon monoxide poisoning last? Carbon monoxide gas enters the body through the lungs through breathing, and it exits the body in the same fashion. It is estimated that someone who has been poisoned by CO gas requires four to six hours to exhale roughly 50 percent of the inhaled carbon monoxide that is in their bloodstream once they are removed from the toxic area and getting fresh air. (2)
Ways to Prevent Poisoning
Carbon monoxide poisoning symptoms can be subtle, but if you have any suspicion that you may have carbon monoxide poisoning you must treat it as a life-threatening medical emergency because it certainly is one. If you think you or someone you’re with may have carbon monoxide poisoning, get outdoors in fresh air immediately and seek emergency medical care.
There is no natural treatment to perform at home for carbon monoxide poisoning, but here are some of the best, expert-recommended ways to prevent it in the first place:
1. Carbon Monoxide Detectors
What does carbon monoxide smell like? The scary fact is that carbon monoxide doesn’t smell like anything! That’s why carbon monoxide detectors are so incredibly necessary and they’re not hard to find. For starters, your local hardware store is very likely to carry a detector if not several detector options. You can also find carbon monoxide detectors online, but always make sure that you are purchasing a detector that is certified by a testing lab.
Detectors should be installed on every level of a home and definitely outside of all bedrooms or sleeping areas. They should also be installed in boats and motor homes. It’s recommended to connect multiple alarms so that if one of them senses a problem, they will all sound the alarm. Test detectors monthly to ensure effectiveness. In case it goes off, make sure you have the correct number to call. If you’re unsure of who to call, ask your local fire department. Remember that you should leave the house first and then call for assistance. (11)
Check batteries in detectors at least twice a year. Most carbon monoxide detectors come with a five to seven year warranty so detectors don’t last forever and need to replaced after several years. Most detectors will begin to chirp or signal when they’re nearing the end of their effective life span. (12)
2. Know What Do When a Detector Goes Off
Having a CO detector is essential to prevention, but it’s also vital to know what to do if a carbon monoxide alarm sounds: (13)
- Never ignore a carbon monoxide alarm and do not try to find the source of the gas.
- Immediately move outside to fresh air.
- Call emergency services, fire department or 911.
- Perform a head count to check that all persons are accounted for.
- Do not reenter the premises until emergency responders have given you permission to do so.
3. Appliance Selection and Inspection
When purchasing new appliances, look for appliance brands that are tested and certified as safe by the Underwriters Laboratories (UL), the American Gas Association (AGA), or other recognized certifying organizations. Have fuel-burning appliances professionally installed.
To guard against CO poisoning, you want to buy appliances that vent to the outside, this way the CO gas is going outside rather than staying indoors. You also want to have appliances installed by a professional to decrease the likelihood of CO leakage. (2)
Once you have appliances in your home, make sure you have any fuel-burning ones inspected regularly, preferably at the start of each heating season. What are examples of appliances that should be checked so that they don’t potentially cause a CO problem? The list includes:
- Gas water heaters
- Gas ranges and ovens
- Gas dryers
- Gas or kerosene space heaters
- Oil and gas furnaces
- Wood stoves
In addition to appliances, fireplaces, flues and chimneys should also be checked for any cracking or clogging. (14)
4. Automobile Safety
When CO gas builds up in an enclosed space, like a garage, humans and animals can be poisoned. You should never warm up a vehicle in any enclosed space such as a garage. Don’t even leave a car with the door open running in the garage.
It’s also important to always ensure that the tailpipe of any vehicle is clear. Sometimes a tailpipe can become clogged due to debris, including snow or ice. When a tailpipe is clogged, carbon monoxide gas can then leak into the inside of a vehicle. Children as well as adults should never be left inside a running vehicle while clearing snow or ice off the vehicle.
With the invention of keyless vehicle ignitions, it’s vital to make sure that your vehicle is truly turned off. If you have children, don’t leave keys or openers where they can take them and potentially get into the car without you. Also, keep your car locked to prevent children from being inside a car alone.
Children and adults should not stand behind a running car for multiple safety reasons. Of course, because of the possibility of being run over, but also because of the fact that being behind a running car means a high likelihood of breathing in dangerous exhaust fumes. (15)
5. Heating No-No’s
There are a lot of ways to heat spaces as well as heating devices that when used improperly can lead to carbon monoxide poisoning symptoms. For starters, never use portable flameless chemical heaters indoors. If you have a generator, it should always be positioned outside of your home. The CDC advises that you should never use a generator inside your home, basement or garage or less than 20 feet from any window, door or vent because “fatal levels of carbon monoxide can be produced in just minutes.”
You should also never use a gas range or oven for heating. This is not safe since using a gas range or oven for heating can cause a buildup of carbon monoxide inside your home or camper. You should also never ever burn any type of charcoal indoors because it gives off carbon monoxide as it is burning. (1)
Final Thoughts
- What is carbon monoxide? It’s an odorless, colorless toxic flammable gas, also known as the “invisible killer” that can be deadly to humans and animals.
- Carbon monoxide poisoning symptoms can vary depending on the level and length of exposure.
- People who are sleeping or drunk can die from CO poisoning before they or anyone else realizes they have carbon monoxide poisoning symptoms.
- Do not attempt carbon monoxide poisoning treatment at home; you need to get outdoors immediately and seek emergency assistance. Do not go back into your home until an expert guarantees it is safe.
- If you suspect you have carbon monoxide poisoning symptoms, do not drive yourself to the hospital because you may pass out while driving.