It’s pretty normal to have difficulty breathing every once in a while. For example, you may huff and puff a little more when you take the stairs instead of the elevator, head outside on a brisk winter day or have a stuffy nose. It can also be difficult to breathe if you’re feeling anxious or stressed.

Occasional shortness of breath is usually nothing to worry about, especially when there’s a clear reason for it. Shortness of breath sometimes goes away on its own. At other times, it can be improved with breathing techniques, lifestyle changes or medication.

However, shortness of breath can also be a sign of a serious condition that needs medical attention, sometimes right away. Call 911 if it’s suddenly difficult to breathe and you have chest pain, fainting, nausea, bluish skin, or swelling in your legs or ankles. And be sure to make an appointment with your primary care doctor if it seems like your breathing problems are getting worse.

So, what causes shortness of breath? What does it feel like? And how do you know if shortness of breath is from anxiety? Read on for the answers to these questions and when to seek treatment.

What shortness of breath feels like

Shortness of breath is the uncomfortable sensation where it seems you cannot get enough air into your lungs, and you feel out of breath. With shortness of breath, you may have:

  • Labored breathing – You may have difficulty breathing and it takes more effort than usual to get enough oxygen. As a result, you may wheeze or breathe noisily.
  • Air hunger – You may feel like you’re hungry for air or that you can’t breathe at all.
  • Shallow breathing – This is when you take quick small breaths rather than full deep breaths. Shallow breathing makes it difficult for you to expand your lungs fully and get all the oxygen that your body needs.
  • Other symptoms – You may also feel tightness in your chest, that you need to work harder to breathe, or like your heart is beating too fast.

Shortness of breath can happen at any time

Shortness of breath can happen with or without exertion. You may have breathing difficulties during activities like walking, climbing stairs or exercising, but you can also have shortness of breath while lying down or sitting still. Shortness of breath can start suddenly or develop over months, or it could come and go. There are even different terms that are used for common times that shortness of breath happens.

  • While lying down – Orthopnea is the term used for shortness of breath that starts when you’re lying down.
  • While lying on one side – If you have shortness of breath while lying on one side but not the other, it’s called trepopnea. This can happen if a medical condition is affecting one side of your heart or lungs.
  • After falling asleep – Paroxysmal nocturnal dyspnea (PND) is used for shortness of breath that occurs 1-2 hours after falling asleep.
  • After talking a lot – If you need to take deep breaths after talking a lot, it’s called sighing (or conversational) dyspnea.
  • Shortness of breath while standing that goes away when lying down – Platypnea is the term for this relatively rare medical condition.

Causes of sudden shortness of breath (acute dyspnea)

Acute dyspnea starts suddenly and goes away pretty quickly – within minutes, hours or days. Sudden shortness of breath can happen if your airway becomes blocked (for example, if you’re choking) or following a sudden change in your health or activity level. Acute shortness of breath can be a medical emergency, or it may go away on its own.

Heart conditions that require emergency attention

Heart conditions that cause sudden shortness of breath may need immediate treatment. Call 911 if shortness of breath is combined with chest pain that lasts for more than a few minutes or goes away and comes back. Heart conditions can also cause nausea, fainting, dizziness, fatigue, and swelling in the belly and legs.

  • Heart attack – A heart attack occurs when blood flow to the heart is blocked. Since the heart muscle isn’t getting enough oxygen, it can lead to shortness of breath, chest pain and other symptoms.
  • Heart failure – If you have heart failure, the heart isn’t able to pump correctly. Fluid can build up in your lungs and put pressure on the surrounding tissues, causing symptoms like shortness of breath, swelling and a cough that doesn’t go away.

Lung conditions that require emergency attention

When shortness of breath is caused by lung conditions, it can be an emergency situation. Call 911 if you have sudden chest pain, or if your lips, nails or skin start to turn blue. Lung conditions that cause sudden shortness of breath include:

  • Blood clot in a lung (pulmonary embolism) – Blood clots can travel to your lungs from other parts of your body and get lodged in a blood vessel. This blocks the normal flow of blood, causing shortness of breath and other symptoms.
  • Collapsed lung (pneumothorax) – If your lung collapses, you won’t be able to breathe properly. This almost always follows a traumatic injury.

Severe allergic reactions that require emergency attention

Severe allergic reactions (anaphylaxis) can be life-threatening – reactions can occur within seconds or minutes after exposure. Swelling in the throat can block the airway, making it difficult to breathe. Other symptoms include hives, itchiness, skin that’s pale or flushed, low blood pressure and a rapid, weak pulse.

You should call 911 if you suspect anaphylaxis. If you have an epinephrine autoinjector, use it right away, but still go to the emergency room to get checked out.

Carbon monoxide poisoning which requires emergency attention

Carbon monoxide is an odorless gas made from burning fuels. If there’s too much carbon monoxide in the air, it can lead to carbon monoxide poisoning. This is because your body replaces the oxygen in your red blood cells with carbon monoxide. As a result, your body doesn’t have enough oxygen to work.

Carbon monoxide poisoning causes symptoms like shortness of breath, headache, weakness, dizziness, nausea, vomiting, confusion, blurred vision, loss of muscle control and fainting. If you think you may have carbon monoxide poisoning, immediately head outside for fresh air and then call 911.

The best way to prevent carbon monoxide poisoning is to have carbon monoxide detectors on each level of your home and near each sleeping area. You’ll also want to test them each year and change their batteries when needed.

Asthma flare-up

If you have asthma, your airways are always slightly irritated and overly sensitive to stimuli such as particles in the air, a change in breathing or a shift in the weather. In response to the stimuli, your body may make a large amount of phlegm, cause your airway to swell and the muscles around your lungs to tighten.

These changes make it more likely that you’ll wheeze, cough and feel breathless. An asthma flare-up usually goes away within a couple of hours but can last longer without treatment. If you think you may have asthma, make an appointment with your doctor to talk about medications and other treatment options.

Viruses that affect your lungs

It’s usually harder to breathe if you have a respiratory illness like a cold, the flu, pneumonia or COVID-19. Respiratory illnesses can cause inflammation and mucus buildup in your nose and lungs. This can make it more difficult to breathe, causing shortness of breath and heavy coughing. Your symptoms typically fade as you recover from the illness.

Conditions like a cold or flu often go away with rest and home treatments. But if it’s been a couple of weeks or you have symptoms like a high fever, it’s worth talking to a doctor about. Start an online appointment to get care right away.

Environmental changes

Extreme temperatures, humidity, changes in elevation and air quality can cause shortness of breath and make other medical conditions worse. If shortness of breath is caused by any of these factors, breathing should get better when you change the environment you’re in. For example, if you’re able to go inside and get away from the heat, cold or environmental toxins, you should be back to normal within a couple of hours. If shortness of breath is a sign of altitude sickness, it’s likely to go away on its own as your body adjusts – usually within one or two days.

Exercise

It’s totally normal for a good workout to leave you a little breathless. But if you remain short of breath for more than a couple minutes or it seems like it’s becoming more difficult to recover from exercise, make an appointment with your primary care doctor. Keeping track of your symptoms before the appointment can be helpful in determining the best treatment plan for you.

Shortness of breath can also be a sign of anxiety or a panic attack

If you have a high level of anxiety or experience a panic attack, your body may respond as if you’re in physical danger and release large amounts of adrenaline and other chemicals into your system as part of its natural fight-or-flight response. This increase in chemicals can cause symptoms such as shortness of breath and a racing heartbeat.

If your shortness of breath is related to anxiety or a panic attack, your symptoms will start during or immediately after periods of stress, worry, anxiety or fear. Anxiety-related shortness of breath usually involves rapid, shallow breathing or hyperventilation, but people can experience it differently. If you think anxiety or stress is causing shortness of breath, look for someone to talk to – it could be a friend, family member, your doctor or a mental health specialist.

Causes of shortness of breath that’s ongoing (chronic dyspnea)

If you have chronic shortness of breath, it means that you’ve had breathing difficulties for several weeks or longer. Chronic shortness of breath is usually related to ongoing health conditions and isn’t a medical emergency. But you should make an appointment with your primary care doctor since conditions that cause shortness of breath tend to get worse over time. Some of the more common causes of chronic dyspnea include:

Chronic lung conditions

While some lung problems can be medical emergencies, some lung conditions can cause shortness of breath that doesn’t go away and gets worse over time.

  • COPD (chronic obstructive pulmonary disease) – COPD is a group of diseases that block airflow from the lungs and includes emphysema.
  • Croup – With croup, the upper airway becomes inflamed as part of a viral infection. This narrows the airway and makes it more difficult to breathe. Croup is more common in young children.
  • Interstitial lung disease (ILD) – This is the name for a group of lung conditions that scar the lungs, so they’re unable to expand and contract properly during breathing. This reduced lung function causes shortness of breath. Specific types of ILDs include sarcoidosis and pulmonary fibrosis.
  • Long COVID-19 – Breathing problems are a common long-COVID-19 lung symptom.
  • Lung cancer – Lung cancer causes tumors that can block the airway and damage lung tissue. This limits the lung’s ability to take in oxygen, causing breathlessness.
  • Pleurisy – With pleurisy, the membrane around the lungs is inflamed and it can be painful to breathe. People with pleurisy tend to have shallow breathing and breathe more quickly.
  • Pulmonary edema – This is when there’s excess fluid in the lungs. This makes it harder for your lungs to exchange oxygen for carbon dioxide when you breathe. Since there’s less oxygen coming in, it can lead to breathlessness.
  • Pulmonary hypertension – High blood pressure in the blood vessels in your lungs causes them to narrow. This puts added strain on the heart and lungs, and can cause breathlessness, especially during physical activity.
  • Tuberculosis – Tuberculosis is a bacterial infection that primarily affects the lungs but it’s pretty rare in the United States. It causes symptoms like shortness of breath, a chronic cough, unexplained weight loss and night sweats.

Chronic heart and blood conditions

Some heart and blood conditions cause shortness of breath that gets worse over time. These conditions can include:

  • Anemia – This condition occurs when a person has an abnormally low red blood cell count. As a result, your body may not have enough red blood cells to carry oxygen through your body, causing shortness of breath.
  • Cardiomyopathy – This is a condition when the heart muscle is abnormal. It may be stiff or weak, for example. Cardiomyopathy may make your heart less effective at pumping oxygen-rich blood throughout your body and lead to heart failure.
  • Valvular heart disease – The heart has four major valves that direct blood flow forward through the heart to the lungs and body. These valves may be damaged, becoming leaky, narrowed or both. Valvular heart disease reduces the heart’s pumping efficiency and can contribute to shortness of breath. Valvular heart disease may also contribute to cardiomyopathy and heart arrhythmias.
  • Heart arrhythmia – Heart arrhythmias can make it so your heart isn’t able to pump enough oxygen-rich blood through your body. This can leave you feeling breathless. Other symptoms may include an irregular heartbeat, lightheadedness and a reduced ability to do physical activities.
  • Inflammation in and around the heart – Conditions like endocarditis, myocarditis and pericarditis arise from inflammation and possibly infection in the tissues of the heart. Such conditions may make it difficult for the heart to work at full capacity, contributing to breathlessness. The inflammation can also cause pain. The body’s response to such pain is rapid, shallow breathing, which can further contribute to shortness of breath.

Being very overweight

Being very overweight can change how your body works and cause shortness of breath. If there’s added weight in the chest and belly area, it can affect the body’s ability to take full breaths, even when at rest. Being very overweight can also cause narrowing of your airways and inflammation throughout the body, which makes it more difficult for air to reach all your organs. If you’re very overweight, talk to your primary care doctor about what you can do to improve your health.

Being out of shape

You’re more likely to get breathless during activities if you’re out of shape. The good news is that it’s never too late to enjoy the physical and mental benefits of exercise. If you’re not sure where to start, talk to your primary care doctor.

Shortness of breath treatment depends on the cause of breathing difficulties

Treatment for shortness of breath depends on what’s causing it. If you have an underlying medical condition, we’ll start by treating that first. If breathing difficulties are related to your physical fitness, your doctor will put together a personalized treatment plan to help you improve your overall health. Treatments may include:

  • Medications – Medications can be effective for shortness of breath caused by asthma, COPD, allergies and other conditions. Your doctor will let you know if they’re an option for you.
  • Breathing exercises – Pursed lip breathing is a good one to try. Sit in a chair with your feet flat in the floor. Then breathe in through your nose for two counts, letting the air fill your belly. Pucker your lips, as if you were going to blow out a candle, then exhale through your lips for four or more counts. Deep breathing exercises can also help you manage the stress and anxiety that can affect your heart
  • Physical activity – Most types of exercises can help with shortness of breath. Cardio strengthens your heart and lungs, so they don’t need to work as hard. Strength training can improve posture, build core strength and tone breathing muscles. If you’re overweight, physical activity is often the best way to lose the extra weight that could be making symptoms worse.
  • Quitting smoking – Cigarette smoke can make breathing and lung conditions worse, so it’s best to quit smoking and avoid secondhand smoke.
  • Limit time in challenging environments – Pay attention for breathing problems that follow time in extreme weather or locations where allergens are high. If you’re outside in conditions that affect your breathing, make sure to take it easy and limit your time outside.
  • Change what and how you eat – Consider switching from eating three large meals to smaller ones throughout the day. When your belly is really full it can push up against your lungs and diaphragm, making it more difficult to breathe. Plus, eating more frequently gives you energy throughout the day, so you’re not so tired. Also, pay attention to what you’re eating. A heart-healthy diet is a great option for overall health.
  • Oxygen therapy – Your doctor may prescribe supplemental oxygen if your blood oxygen level is very low and you’re not able to get enough oxygen on your own. It’s delivered through a mask or tube in your nose.
  • Rehabilitation – If breathing problems are related to a chronic condition, pulmonary rehabilitation or cardiac rehabilitation may be recommended to help you manage your symptoms. Physical therapy may be recommended to improve physical fitness if you have shortness of breath while recovering from an injury or medical condition.

When to see a doctor for shortness of breath

See a doctor if you have shortness of breath that’s not expected for the activity and your level of physical fitness. Shortness of breath can be an emergency situation, or it can affect the quality of your life.

When to get emergency care for sudden shortness of breath

If you have sudden, severe shortness of breath that makes it difficult to function, it’s important to get care right away. Call 911 or have someone drive you to the emergency room if you have any of the following:

  • Sudden and severe breathlessness that makes you feel like you can’t catch your breath
  • Breathlessness that continues even after 30 minutes of rest
  • Skin, lips or nails that start to look blue
  • Chest pain or heaviness
  • A fast or irregular heartbeat
  • Wheezing or a high-pitched sound when breathing
  • Other symptoms, such as high fever, or swollen ankles and feet

When to make a doctor’s appointment for chronic shortness of breath

Make an appointment with your primary care doctor if you have chronic shortness of breath that’s getting in the way of your daily life or becoming worse. Your doctor will help identify the reason for your shortness of breath and put together a treatment plan. If appropriate, they’ll refer you to a specialist such as a cardiologist or a pulmonologist for additional treatment.