Symptoms of carbon monoxide poisoning include headaches, dizziness, weakness, vomiting, chest pain, and confusion.
Excessive exposure to CO can lead to severe heartbeat irregularities, seizures, unconsciousness, and even death.
This article discusses the symptoms of carbon monoxide poisoning and how its diagnosed.

Verywell / Emily Roberts
It also discusses how its treated and ways to prevent it.
Initial carbon monoxide poisoning symptoms typically include nausea, malaise, fatigue, and a dull but persistent headache.
How Long Does Carbon Monoxide Poisoning Take to Show Symptoms?

© Verywell, 2018
Carbon monoxide poisoning can be fatal within minutes.
Causes
Carbon monoxide easily enters the body through the lungs.
By doing so, CO prevents oxygen from getting to the tissues and cells that need it to survive.
Carbon monoxide is a natural byproduct of combustion.
Similar, idling your car in winter can poison passengers if the exhaust pipe is blocked with snow.
Any perforation in the exhaust manifold of a car or boat can allow CO to flood the interior.
Carbon monoxide poisoning may also occur intentionally.
It involves a non-invasive probe, called a CO-oximeter, which measures CO compounds in the blood.
The unit can be placed on your finger, toe, or other parts of the body.
The oximeter contains two diodes that emit light beams of different wavelengths.
Under normal circumstances, you would have less than 5% carboxyhemoglobin compared to free hemoglobin.
Generally, poisoning occurs if the level is above 10%.
Death can occur at levels over 25%.
Even if symptoms are mild, emergency medical treatment should be sought.
Treatmentmay involve the administration of pressurized oxygen through a non-circulating mask.
Hyperbaric oxygen clears CO from the blood faster than oxygen delivered at normal atmospheric pressure.
First and foremost, do not look for the source of gas.
Exposure to very high levels of carbon monoxide may induce hallucinations.
Early symptoms of carbon monoxide poisoning are often described as flu-like.
This includes symptoms like headache, dizziness, weakness, upset stomach, and chest pain.
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U.S. Consumer Product Safety Commission.Carbon monoxide fact sheet.