What are the Symptoms of Carbon Monoxide Poisoning?

The symptoms of Carbon Monoxide Poisoning are very ordinary. They can be easily confused for other medical conditions and missed by healthcare providers who are not alerted to the possibility that Carbon Monoxide Poisoning may have occurred. That is why it is important to know what is going on around your home, at work and in your vehicle or boat. If you get sick and go to the hospital make sure you raise the possibility of Carbon Monoxide Poisoning so that it is not missed by your healthcare provider.

In the winter, Carbon Monoxide Poisoning is on the minds of healthcare providers because of the use of fireplaces, heaters, and generators. However, it quickly fades from their minds once the winter season is over. Along the Gulf Coast and Atlantic Coast of the United State Carbon Monoxide Poisoning is on the minds of healthcare providers during hurricane season, again because of the use of generators after storms.

It is very important to remember that Carbon Monoxide Poisoning is not a seasonal or weather related condition, but is one that can occur at anytime and anywhere. When in doubt raise the issue with your healthcare provider so that they can run the necessary tests to ensure that you have not been poisoned by Carbon Monoxide and they can get you the appropriate treatment as soon as possible. There is a limited window of time within which Carbon Monoxide Poisoning can be treated. If that window is missed there is a strong likelihood that you may have long lasting effects for the rest of your life.

The symptoms of Carbon Monoxide Poison are very similar to that of the flu.  Initially you may develop a slight headache, fatigue (feel tired), shortness of breath. You may even feel some nausea (like you want to throw up). You also may feel dizzy and confused. Depending upon your time of exposure these symptoms may get worse or they might go away all together after you leave the area of exposure.

If, for example, the area of exposure is in your home you may actually feel better when you get to work. The reason for this is that you are no longer being exposed to the Carbon Monoxide. You are breathing in uncontaminated air and your body is expelling the Carbon Monoxide from your system. Your organs and tissue are getting more oxygen. However, as soon as you return home, depending upon the concentration of Carbon Monoxide you will begin to develop your symptoms all over again and they may even get worse.

The following chart will give you a general idea of the symptoms you may feel at certain levels of exposure. This chart is not definitive, as each person does react differently to Carbon Monoxide at lower levels. At higher levels of exposure there is not much difference in how a person will react to being exposed to Carbon Monoxide (CO). 

ppm = parts per million 

How Carbon Monoxide effects an individual depends heavily on the concentration of Carbon Monoxide that individual was exposed to and the length of time of the exposure. There are two types of Carbon Monoxide Poisoning Exposures, Acute (Short Term) and Chronic (Long Term). An Acute Carbon Monoxide Poisoning is one that lasts less than 24 hours and a Chronic Carbon Monoxide Poisoning is typically viewed as being multiple exposures lasting 24 hours or more.  

In an Acute Carbon Monoxide Poisoning situation, typically a person is exposed to high levels of Carbon Monoxide over a period of time (less than 24 hours) that results in significant carboxyhemoglobin concentrations in their blood. An example of an acute exposure would be when a person is driving their car and there is a leak in their exhaust system that allows high levels of carbon monoxide to build up rapidly in the passenger compartment of their car. They will develop symptoms quickly and if not removed from that environment and treated can pass out or even die. 

In a Chronic Carbon Monoxide Poisoning situation (typically multiple exposures lasting 24 hours or less) a person is exposed to lower levels of the Carbon Monoxide in the air and have lower carboxyhemoglobin concentrations in their blood. An example of a Chronic Exposure would be a leaky boiler in your home. Over time the concentration levels of Carbon Monoxide would build up in your home and you would develop symptoms. The symptoms might be as benign as a mild headache and eventually build up to nausea, confusion and collapse. 

A person suffering from Chronic Carbon Monoxide poisoning may not have the typical symptoms of an Acute Carbon Monoxide Poisoning victim, such as headache, nausea, weakness, dizziness, etc. the person suffering from Chronic Carbon Monoxide Poisoning will often be misdiagnosed as having chronic fatigue syndrome, a viral or bacterial pulmonary or gastrointestinal infection, a "run-down" condition, or immune deficiency. The problem is that lower level Carbon Monoxide Poisoning mimics the flu. Many people suffering Chronic Carbon Monoxide Exposure do not even know it is occurring and as such they do not associate their severe headache and nausea a carbon monoxide exposure. At moderate concentrations, a Carbon Monoxide Exposure can result in angina, impaired vision, and reduced brain function. At higher concentrations, carbon monoxide exposure can be fatal.  

The main reason carbon monoxide is such a poisonous substance is the strength in bonding a Carbon Monoxide molecule has over Oxygen. A Carbon Monoxide molecule has at least three times the bonding ability than an oxygen molecule. What that means is that when you inhale Carbon Monoxide along with Oxygen, the Carbon Monoxide will bond to the hemoglobin in your blood three times more than the Oxygen. That will result in your body getting less oxygen than it needs. Over time this lack of oxygen will cause the cells within your body to begin to shut down and result in the symptoms discussed above.  

If you suspect that you have been exposed to Carbon Monoxide and may be suffering the effects of Carbon Monoxide Poisoning it is important that your healthcare providers get you a blood test that evaluates the level of Carbon Monoxide in your blood. This blood test looks at the carboxyhemoglobin levels in your blood to determine the extent of your exposure. As discussed above carboxyhemoglobin is the result of the stronger bonding ability of Carbon Monoxide over Oxygen. The higher the concentration of your exposure the more carboxyhemoglobin there will be in your blood. The percentage of carboxyhemoglobin in your blood will provide your healthcare providers necessary information to properly treating your condition.  

If you do not ask your healthcare provider to test for carboxyhemoglobin typically they will not do so on their own. It should be done as soon as possible from the time of suspected exposure, as the signs of carbon monoxide usually leave the blood stream within hours. If you have been given oxygen by healthcare providers before the blood test is performed, the results of the test will not be accurate. This is because carboxyhemoglobin leaves the body faster when an individual is on oxygen. You should be aware of this, as even though the carboxyhemoglobin may leave your body in several hours, the damage that it causes to the brain, heart and nervous system won’t. 

Typically Carboxyhemoglobin has a half-life of four (4) to five (5) hours, which means that the longer after a suspected exposure you wait to get tested the less accurate the carboxyhemoglobin levels will be. The closer in time that a blood test can be run, the more accurate the test will be in determining the level of your exposure. In most cases the carboxyhemoglobin levels will drop back down to background levels (meaning normal levels not indicating an exposure) in twenty-four (24) hours. 

There is some scientific research that currently suggests that a “soaking” phenomenon occurs in chronic exposures to Carbon Monoxide. Basically, what happens is that over the time of the chronic exposure, the level of carbon monoxide in a person’s system increases because their body cannot remove all of the Carbon Monoxide it has ingested before being exposed to more Carbon Monoxide.   

For example, if a person is working in a warehouse that is enclosed and is utilizing propane powered forklifts to move items around the warehouse, there is a strong possibility that exhaust could build up inside. If the warehouse is poorly ventilated, overtime the exhaust (including Carbon Monoxide) builds up to a point where it will start to physically impact this person. This individual while inside the warehouse will build up a certain level of Carbon Monoxide in their blood and have physical symptoms as a result of this build up. Once they leave the warehouse the concentration of carbon monoxide in their blood will start to go down and given sufficient time it will be back down to normal levels.  

However, if the time away from the warehouse is not long enough, the carbon monoxide levels in the body will not go back to normal, but will remain somewhat elevated. So when they go back to work the next day, they will be starting off with elevated levels of carbon monoxide in their body and will build back up the concentration of Carbon Monoxide in their blood more rapidly once they start working in the warehouse again. As such, there will be a cumulative effect over time on the level of their carbon monoxide in their body and the damage it is causing.  

Remember this is a very simplistic explanation of Carbon Monoxide Poisoning and does not provide all of the detailed information you will get from your medical providers. The purpose of the explanations in this book are to give you a basic idea of how Carbon Monoxide Poisoning occurs and what you need to watch out for to protect yourself if you find yourself being exposed to Carbon Monoxide. 

It cannot be stressed enough, if you suspect that you are being exposed to Carbon Monoxide medical attention immediately! If you are noticing symptoms such as short term memory loss, loss of balance, severe headaches, or other unusual symptoms you may have been exposed to carbon monoxide. If you believe that you have been exposed to carbon monoxide, get medical attention as soon as possible to prevent or reduce permanent damage.