Health Topic

Carbon Monoxide Poisoning

Carbon monoxide is known as the silent killer. It is a deadly gas that has no color or smell. Protect yourself and your family by learning more.

Reviewed Reviewed by a registered pharmacistGeneral information

Also called: CO poisoning

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Carbon Monoxide Poisoning

Carbon monoxide (CO) is a gas that has no odor or color. But it is very dangerous. It can cause sudden illness and death. CO is found in combustion fumes, such as those made by cars and trucks, lanterns, stoves, gas ranges and heating systems. CO from these fumes can build up in places that don't have a good flow of fresh air. You can be poisoned by breathing them in. The most common symptoms of CO poisoning are:

  • Headache
  • Dizziness
  • Weakness
  • Nausea
  • Vomiting
  • Chest pain
  • Confusion

It is often hard to tell if someone has CO poisoning, because the symptoms may be like those of other illnesses. People who are sleeping or intoxicated can die from CO poisoning before they have symptoms. A CO detector can warn you if you have high levels of CO in your home.

Centers for Disease Control and Prevention

It sits within Poisoning, Toxicology, Environmental Health.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Carbon Monoxide Poisoning

46 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

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Prevention and Risk Factors

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Carbon Monoxide Poisoning. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Carbon Monoxide Poisoning, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.