Sleep apnea is a common—and potentially serious—breathing disorder in which your breathing stops or becomes shallow during sleep. Early recognition and treatment is important since sleep apnea may be associated with other conditions, such as irregular heartbeat, high blood pressure, heart attack, and stroke. There are two types of sleep apnea. Obstructive sleep apnea is the most common type and happens when air can’t flow into or out of your nose or mouth. Central sleep apnea is when your brain fails to send the right signals to your muscles to start breathing. If you have sleep apnea, your breathing may be interrupted as many as 20 to 30 or more times per hour. During these pauses, you are unable to breathe in air and the level of oxygen in your blood drops. You might snort, choke, or gasp for air as you go back to breathing normally. These frequent arousals prevent you, and often your sleep partner, from getting enough restorative, deep sleep, which often leads to early morning headaches and excessive daytime sleepiness. In obstructive sleep apnea, shallow breathing or a pause in breathing happens because tissue narrows or blocks part of your airway—your nose, mouth, throat, and windpipe. For instance, your tongue or tonsils might clog your airway; your airway might close up when your throat muscles relax; or extra fat around your windpipe might make the space inside it smaller. Sleep apnea happens at any age and can occur in both men and women. People most likely to have or develop sleep apnea include those who snore loudly, are overweight, and have high blood pressure. People with physical abnormalities in the nose, throat, or other parts of the upper airway are also at risk. Most people with sleep apnea don’t know they have a problem because they are asleep when it happens. A family member may be the first to point out the signs. People with sleep apnea may snore loudly and may feel sleepy during the day because their nighttime sleep is disrupted. Without treatment, sleep apnea raises your risk for high blood pressure, heart attack, stroke, diabetes, and obesity. Because it leads to daytime sleepiness, it can also increase the chance for accidents at work or while driving. If you suspect you have sleep apnea, you doctor may recommend testing to make a diagnosis. Polysomnography is testing that records your body functions during sleep, including the brain’s electrical activity, eye movement, muscle activity, heart rate, respiratory effort, air flow, and blood oxygen levels. A multiple sleep latency test measures how fast you fall asleep. Tests are usually performed in a sleep center, but new technology may mean some sleep studies can happen right in your home. Therapy for sleep apnea is specifically designed for each patient. Lifestyle changes are an important part of treatment and in some cases may be all that is needed. You may need to lose weight if you’re overweight; avoid drinking alcohol before sleep; avoid using tobacco and sleeping pills; and use pillows and other devices to help you sleep on your side. Some patients wear masks during sleep that deliver fresh air through the nasal passages. Mouthpieces that reposition the lower jaw and tongue may help some people with mild sleep apnea. Other people with sleep apnea may need surgery. Your doctor will determine the best treatment option for you.