Symptoms of CO Poisoning

The symptoms of carbon monoxide poisoning are not always obvious, and this is especially true of low-level exposure – indeed some researchers believe we still have much to learn about the true effects of long term low-level carbon monoxide exposure.

Low Level Carbon Monoxide Exposure

At low levels symptoms can be similar to many other conditions such as food poisoning and colds. However, unlike colds and flu, carbon monoxide poisoning does not cause a high temperature.

The most common symptoms include:

Headache
Nausea and vomiting
Dizziness
Tiredness and confusion
Stomach pain
Shortness of breath

Symptoms may be less severe away from the source of the carbon monoxide, and this would be another key reason to suspect a carbon monoxide problem.

The longer carbon monoxide is inhaled the worse the symptoms will be, including loss of balance, vision, memory and, eventually, consciousness.

Long-term exposure to low levels of carbon monoxide can also cause neurological effects, such as:

poor concentration
sudden or unusual emotional changes, such as irritability, depression or impulsiveness

High Level Carbon Monoxide Exposure

Inhaling high levels of carbon monoxide is likely to produce more severe symptoms such as:

impaired mental state (such as apparent drunkeness)
vertigo (the room spinning)
poor physical co-ordination
tachycardia (heart rate of more than 100 bpm)
chest pain
seizures
loss of consciousness and death

High Risk Groups

Some people may be affected by carbon monoxide poisoning more quickly or seriously than others. Those at higher risk include:

babies and young children
pregnant women
those with heart or breathing problems

The smaller an animal or a person is, the faster carbon monoxide will affect them, so pets may be the first to show signs of carbon monoxide poisoning. Indeed, if a previously healthy pet suddenly becomes ill or dies, and death is not related to old age, testing for carbon monoxide should be carried out immediately.