A poisoned state in which carbon monoxide gas has been breathed and soaked up by the blood. Too much carbon monoxide limits the ability of the blood to transport oxygen. This can result in headache, loss of sleep, trouble breathing, and death. In a small enclosed space, death can occur within minutes unless emergency treatment is given. A sign of carbon monoxide poisoning in a patient is a cherry-pink skin color. It is treated by removing the patient from the source right away and giving oxygen.