A nasal cannula is a small tube that oxygen patients use to inhale medical oxygen. A standard cannula has two “prongs” that will fit into a patients nose, most cannula have a seven foot hose that can attach to any barb on either an oxygen regulator or a concentrator. The use of a nasal cannula is beneficial for patients who use oxygen because it puts the oxygen right at their nostrils. A nasal cannula can be used 24 hours a day and patients who do not breathe through their noses while sleeping. Nasal cannulaes can sometimes cause irritation to your nose or the inside of your nose.