context: Your body can't live without the oxygen you breathe in from the air. But if you have lung disease or other medical conditions, you may not get enough of it. That can leave you short of breath and cause problems with your heart, brain, and other parts of your body. Oxygen therapy can help. It's a way to get extra oxygen for you to breathe. Oxygen is a prescription medication. Home oxygen therapy can help with many conditions, including: Asthma Chronic bronchitis Congestive heart failure COPD (chronic obstructive pulmonary disease) Cystic fibrosis Emphysema Lung cancer Pneumonia Pulmonary fibrosis Sleep apnea Your doctor will give you a prescription that spells out how much oxygen you need per minute and when you need to get it. Some people may need oxygen therapy only when they exercise or sleep. Others may need it all day long. Your doctor will figure out how much extra oxygen you need after they check your usual levels, either with a blood test or through the skin using a device that clips to your finger, toe, or earlobe. You can get oxygen in several ways. The best choice for you depends on how much you need, your lifestyle, and other things. Standard oxygen concentrator. This machine has a motor and runs on electricity or sometimes batteries. It takes in regular air and filters out other gases to get the oxygen. It weighs about 50 pounds and usually has wheels so you can move about while you're hooked up to it. If you have the plug-in kind, you'll need a backup source of oxygen in case the power goes out. Portable oxygen concentrator. This is a good choice for when you run errands or go to work. It weighs 3-20 pounds so you can carry it. You can plug some models into your car or run them on battery packs. Liquid oxygen tank. Usually, oxygen is a gas. But at lower temperatures it becomes a liquid. It takes up less space than gas, so you can store a lot more liquid oxygen in a thermos-like tank. When it comes out, the liquid converts to a gas right away so you can breathe it in. A tank can weigh more than 100 pounds, and you need to refill it every few weeks. You can also fill up a smaller canister that's easy to carry when you leave the house. Compressed oxygen gas tank. This is an older and less common choice. It squeezes, or compresses, oxygen under high pressure inside a metal cylinder or tank. It's very heavy, and the tank can't be moved. You replace empty tanks every few days. Compressed gas also comes in smaller, portable cylinders, but they only last a short time. You will also need a way to breathe in the oxygen. You can use a: Nasal cannula. This is a soft plastic tube with two small prongs at one end. They go in your nose, and the tube rests over your ears to hold it in place. The other end connects to your oxygen supply. The nasal cannula delivers steady oxygen. It can dry your nose out a little. Face mask. This fits snugly over your mouth and nose. The mask can make it hard to talk, and you can't wear it while you eat or drink. Usually, you would use a mask to get high levels of oxygen. Transtracheal catheter. For this surgery, your doctor inserts a small plastic tube called a catheter through your neck just below your Adam's apple and into your windpipe. A necklace holds the tube in place. The other end connects to your oxygen supply. You can't see the catheter if your shirt is buttoned to the top. Another advantage is that you need a smaller oxygen flow since it goes directly into your airway. But it has several drawbacks. One is that the opening in your neck could get infected. Oxygen is a safe gas, but it will make something else burn hotter, brighter, and more easily. Always follow these safety tips around oxygen: Never smoke, and don't let others light up near you. Keep away from open flames, such as matches, cigarette lighters, and burning tobacco. Stay 5 feet away from heat sources. That includes gas stoves, candles, lighted fireplaces, and electric or gas heaters. Don't use flammable products like cleaning fluid, paint thinner, and aerosol sprays. Keep oxygen containers upright. Attach them to a fixed object so they don't topple. Skip products with oil, grease, or petroleum. That also goes for petroleum-based creams and ointments like Vaseline on your face or upper chest. Have a fire extinguisher close by. Let your fire department know that you have oxygen in your home. Tell your electric company if you use an oxygen concentrator so you get priority service in case of a power failure.