Symptoms of Carbon Monoxide Poisoning

The symptoms of carbon monoxide poisoning can be very non-specific, often resulting in them being mistaken for flu or even food poisoning.

The symptoms of CO poisoning can vary from person to person and can also depend upon the levels of exposure and how much carbon monoxide is breathed in.

It is easy to see how these symptoms can be confused with more common ailments such as flu or food poisoning, as they are very general symptoms.

And because of the non-specific nature of these symptoms, many people each year continue to breathe in carbon monoxide obliviously, which can eventually lead to far more serious, long-term symptoms and damage, or even death.

In general, individuals who have been exposed to carbon monoxide experience headaches, dizziness, fatigue, muscular pains, and stomach aches. Carbon monoxide gas has no odor or taste, so many people do not know that they have been exposed to the deadly chemical and do not seek treatment.

The amount of carbon monoxide a person has been exposed to is one of many determining factors in the severity of the symptoms they experience.

Other important factors include the victim’s age, gender, and overall health.

Carbon monoxide poisoning symptoms:

There are some common symptoms of carbon monoxide poisoning, some of which are listed below.

Exposure to low levels of carbon monoxide (CO) may result in the following symptoms:

  • Difficultly breathing;
  • Chest Pain;
  • Fatigue;
  • Headaches:
  • Nausea.

Upon exposure to a small amount of carbon monoxide, an individual should go outside immediately and get fresh air, which may lessen the symptoms. Inhalation of clean air will remove some of the carbon monoxide that has entered the bloodstream, therefore allowing the body to return to the normal level of oxygen in the blood.

Exposure to moderate levels of carbon monoxide may result in the following symptoms:

  • Angina;
  • Coma;
  • Coordination difficulties;
  • Difficulty moving;
  • Weakness;
  • Hypothermia;
  • Low blood pressure;
  • Memory loss;
  • Problems with brain functions;
  • Respiratory failure;
  • Vision impairment.

Exposure to high levels of carbon monoxide can cause death

There are some differences between the symptoms of carbon monoxide and the symptoms of flu, and you should make sure that you are aware of these differences as they may help to save your life.

Unlike flu, carbon monoxide poisoning does not produce feverish symptoms or glandular swelling. Although you may suffer symptoms of general fatigue you should not experience the same aching sensation with carbon monoxide as you often would with flu.

The symptoms of carbon monoxide poisoning may also come and go, or seem more severe on some occasions than on other. Flu, on the other hand, is usually continual until it has passed. With carbon monoxide poisoning you may find that your symptoms worsen at particular times of the day or in particular places.

Carbon monoxide poisoning usually peaks in winter time, when people burn various types of fuel in order to keep warm.

The causes of carbon monoxide poisoning include the incomplete burning of carbon-based fuel and materials as well as faulty equipment and poor ventilation. This makes the colder season a far greater risk period than other times of the year, as it is during the cold season when most people in crease their use of fuel burning equipment.

Classification of Carbon Monoxide Poisoning Symptoms:

  • I – Mild
    Headache, vomiting, tachycardia, no disturbances of consciousness;
  • II – Moderate
    Disturbances or loss of consciousness without other neurological symptoms, tachycardia, nocioceptive reflexes still intact;
  • III – Severe
    Loss of consciousness, intense muscular tonus, pathological neurological symptoms, tachycardia and tachypnea, circulatory and respiratory disturbances not observed;
  • IV – Very Severe
    Loss of consciousness, clinical signs of central nervous system damage, circulatory and respiratory disturbances.
    (From: Jain, K.K. 1990, Carbon Monoxide Poisoning, Warren H. Green, Inc., St. Louis, MO)

If you have experienced any symptoms of carbon monoxide poisoning you should seek medical assistance immediately and have a CohB test performed as soon after the exposure as possible, as carbon monoxide will clear the blood stream in a very short amount of time. This is an effective means of determining the amount of carbon monoxide in your body.

The levels of carbon monoxide that are in your body deplete quickly, therefore you should get tested as soon as possible so that the doctor can get accurate results. If you suspect that the source of the possible carbon monoxide exposure is your home, you should go directly from your home to the doctor so that your test will show the highest amount of CO that is in your body.

In addition to a CohB test, there are many other tests that can be conducted to detect carbon monoxide in the body, including an electrocardiogram, Glasgow coma scale, chest x-ray, electroencephalogram, MRI, and a blood count.

Signs of carbon monoxide poisoning

It is important to always stay vigilant for any signs of carbon monoxide poisoning, particularly if you use carbon-based fuel or equipment that could post a CO risk. If several members of the family begin to display similar symptoms, it is vital that you seek assistance immediately. The same applies if you notice that pets are starting to show signs of illness as well.

You should also ensure that you minimise on the risks of carbon monoxide poisoning by taking precautionary steps, as these could save you from serious risk of death or permanent damage.

However, even if you have taken precautions such as CO detectors and regular equipment checks, this will not make you immune to CO poisoning, and it is still vital that you remain aware of the symptoms and seek assistance should you have any doubts or worries.


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