Carbon Monoxide Poisoning - Topic Overview

Topic Overview

What is carbon monoxide poisoning?

Carbon monoxide poisoning happens when you breathe too much carbon monoxide. Carbon monoxide is a gas produced by burning any type of fuel—gas, oil, kerosene, wood, or charcoal. What makes carbon monoxide so dangerous is that when you breathe it, it replaces the oxygen in your blood. Without oxygen, cells throughout the body die, and the organs stop working.

You can't see, smell, or taste carbon monoxide. But if you breathe too much of it, it can become deadly within minutes. So it’s very important to know the signs of carbon monoxide poisoning, what to do if you have the symptoms, and how to keep it from happening.

What causes carbon monoxide poisoning?

Carbon monoxide can come from any source that burns fuel. Cars, fireplaces, powerboats, woodstoves, kerosene space heaters, charcoal grills, and gas appliances such as water heaters, ovens, and dryers all produce carbon monoxide. Usually they cause no problems. Trouble comes when:

• Cars, trucks, or other engines are left running in enclosed spaces, such as garages. Carbon monoxide can build up in a garage and leak back into the house. Even sitting in an idling car in an open garage or swimming behind an idling boat can be dangerous.
• Fuel-burning appliances are not installed or used properly. Dangerous levels of carbon monoxide can build up inside houses and other buildings.
• Fuel-burning heating systems and appliances are used during cold weather, when doors and windows are closed. Chimneys in older buildings become blocked and release fumes into the homes or offices. Newer houses that are well insulated and tightly sealed can trap carbon monoxide inside living areas.

What are the symptoms?

Early symptoms of carbon monoxide poisoning include:

• Headache.
• Dizziness.
• Nausea.

If you have these symptoms and there is a chance they could be caused by carbon monoxide poisoning, leave the area right away and call 911 or go to the emergency room. If you keep breathing the fumes, you may pass out and die.

Carbon monoxide poisoning can occur suddenly or over a long period of time. Breathing low levels of carbon monoxide over a long period can cause severe heart problems and brain damage. See a doctor if:

• You often are short of breath and have mild nausea and headaches when you are indoors.
• You feel better when you leave the building and worse when you return.
• Other people you work or live with have the same symptoms you do.

How is carbon monoxide poisoning diagnosed?

If your doctor suspects carbon monoxide poisoning, he or she can order a blood test that measures the amount of carbon monoxide in your blood. You may have other blood tests to check your overall health and to look for problems caused by carbon monoxide poisoning.

It can be hard to know if you have carbon monoxide poisoning. The same symptoms can be caused by flu or other problems. In the winter months, doctors may suspect carbon monoxide poisoning in people who complain of severe headache, nausea, or dizziness. This is especially true if other household members or coworkers have similar symptoms.

How is it treated?

The best treatment is oxygen therapy. Breathing pure oxygen can bring the oxygen level in the blood back to normal. There are two kinds of oxygen therapy:

• 100% oxygen therapy, in which you breathe oxygen through a tight-fitting mask. This is the most common type of oxygen therapy.
• Hyperbaric oxygen therapy. For this treatment, you lie in a full-body chamber that delivers oxygen under high pressure. This quickly reduces carbon monoxide levels in the blood.

With quick treatment, most people recover within a few days. But long-term problems can show up later. It is important to tell your doctor about any changes in vision, coordination, or behavior that occur in the weeks after treatment.

How can you prevent carbon monoxide poisoning?

Many people die every year from accidental carbon monoxide poisoning. There are some important steps you can take to reduce your risk.

• Have all fuel-burning appliances (such as oil or gas heaters, stoves, water heaters, and space heaters, fireplaces, and wood stoves) inspected each year.
• Check chimneys, flues, and vents regularly to make sure they are in good shape, properly connected, and not blocked.
• See a doctor right away if you think you have symptoms of carbon monoxide poisoning, especially if more than one person has the same symptoms.

Know how to avoid carbon monoxide poisoning when you operate a vehicle:

• Do not leave your car running in the garage, even if the garage door is open.
• Do not ride in the back of a pickup truck with a camper shell.
• Do not swim behind an idling boat.

Be safe when you use fuel-burning tools or appliances:

• Never use a kerosene or propane heater in an enclosed area, such as a camper, motor home, trailer, or tent.
• Never use a gas or charcoal grill indoors.
• Never use a gas oven to heat your home.
• Do not close a fireplace or stove damper before the fire is completely out.
• Do not use gas-powered generators, lawn equipment, or engines in enclosed areas.

Consider putting carbon monoxide detectors in your home near sleeping areas. Look for ones endorsed by Underwriters Laboratory (UL). If you install carbon monoxide detectors:

• Be sure to follow the directions carefully, and know what to do if the alarm sounds.
• Understand that carbon monoxide detectors are a backup safety measure. They do not replace the need to check appliances regularly and use them safely.

Frequently Asked Questions