Mother holding young daughter Most of us are aware that carbon monoxide (CO) is a dangerous gas with no detectable odor. Many of us live in homes with smoke detectors that are also designed to detect CO. But those detectors don’t always work, and CO poisoning can also occur outside your home, especially in your car, and in spaces without CO detectors.

Do you know the signs of CO poisoning and how to prevent exposure to this gas?

Symptoms of carbon monoxide poisoning

“When there is too much CO in the air you breathe, the gas replaces the oxygen in your red blood cells,” says Blair Thornley, PharmD, a specialist in the Poison Control Center at Children’s Hospital of Philadelphia (CHOP). “That reduces the amount of oxygen your blood can carry and the amount of oxygen delivered to your vital organs.” The organs at greatest risk of injury are those with the highest requirements for oxygen — the heart and the brain. The very young and the very old are most sensitive to the effects of CO.

Early symptoms of exposure to CO, after breathing it for a short time, include:

  • Dull headache
  • Shortness of breath during mild exertion
  • Weakness or fatigue
  • Dizziness

Continued exposure to CO may result in:

  • Nausea or vomiting
  • Visual disturbances, such as blurred vision
  • Difficulty concentrating

Prolonged exposure and lack of medical treatment may lead to serious and long-term effects and may even be life-threatening.

Is it carbon monoxide poisoning or the flu?

Thornley notes that many of these symptoms — headache, dizziness, nausea and fatigue — can be confused with the common flu. How can you tell if what you or your children are experiencing is CO poisoning rather than the flu?

  • “Flu is passed from one family member to another, and usually does not affect everyone in the family at the same time,” says Thornley. “If everyone in your home or in your car, including pets, begins to feel these signs of sickness within a short amount of time, be alert to the possibility of CO poisoning.”
  • “Symptoms of the flu do not improve after leaving the affected space, and are usually relieved with proper medication,” Thornley continues. “If the symptoms improve when you go outside, or are not relieved with medication, you may be experiencing CO poisoning.”

What to do when you suspect carbon monoxide poisoning

If CO is detected with an alarm device, or if you suspect from your symptoms that you or your family members have been exposed to CO, leave the area of exposure immediately and go to the emergency department. Call the Poison Control Center at 1-800-222-1222 for further instruction. The gas company, oil company or local health authority can provide help in identifying and removing sources of CO contamination.

Preventing carbon monoxide poisoning

Fuel-burning products and engines produce carbon monoxide, as do some chemical products, such as paint strippers. When engines are working properly and CO-producing products are used with appropriate ventilation, they aren’t normally a cause for concern. But when an engine’s exhaust is blocked in some way, or if CO-producing products are used in a closed space, the carbon monoxide can build to dangerous levels.

Follow these recommendations to help prevent carbon monoxide poisoning:

  • Install a battery-operated or battery back-up CO alarm in the home and replace the batteries every year.
  • Place generators as far from homes as possible (minimum of 25 feet), but also at a safe distance from any nearby dwellings.
  • Never leave a car running in the garage or another enclosed space. CO can accumulate even when the garage door is open.
  • Never use a generator, grill, camp stove, or other gasoline or charcoal-burning device inside a home, basement, garage, or outside near an open window.
  • Never heat homes with a gas oven or by burning charcoal.
  • Ensure that fuel-burning space heaters are properly vented.
  • Maintain your heating system, water heater, and any gas, oil, or coal burning appliances with annual service appointments with a qualified technician.
  • Do not use portable flameless chemical heaters indoors. These types of heaters burn gas and can cause CO to build up inside your home.
  • Leave the building and dial 911 if a CO alarm sounds, if CO poisoning is suspected, or if any person begins to feel dizzy, light-headed or nauseous.
  • After a major snowstorm, your car's exhaust pipe may be blocked by snow, causing the gas to back up into the car. To protect yourself and your passengers from carbon monoxide poisoning, avoid being in the car with the engine running when there is a risk of your tail pipe being blocked.

For suspected cases of CO poisoning and other exposures, call your regional poison center at 1-800-222-1222.

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