Pneumothorax is a condition where air enters the space between your lung and chest wall, causing the lung to collapse partially or fully. This can lead to sudden chest pain and difficulty breathing, and while it can happen to anyone, it affects certain groups more than others.

Understanding How Common Pneumothorax Is

Pneumothorax affects roughly 20 people per 100,000 each year, making it a relatively uncommon but significant medical condition. The condition does not affect everyone equally—it shows clear patterns in who is most likely to experience it.^[1][3]

Men are significantly more likely to develop pneumothorax than women. When looking at the type called primary spontaneous pneumothorax (which means the lung collapses without an obvious cause in otherwise healthy people), it most commonly affects young adults, particularly men between the ages of 20 and 40 years old. These individuals often share certain physical characteristics—they tend to be tall and thin.^[3][5]

The condition can also develop in people who have existing lung diseases. This is called secondary spontaneous pneumothorax, and it occurs in individuals whose lungs are already weakened by conditions like chronic obstructive pulmonary disease, asthma, or cystic fibrosis. In these cases, the damaged lung tissue makes it easier for air to leak into the chest cavity.^[3]

Another form of pneumothorax happens due to injuries or medical procedures. This traumatic pneumothorax can occur after car accidents, stab wounds, or even during medical treatments like inserting a central line or performing a lung biopsy. Anyone undergoing these procedures faces some risk, though it remains relatively low.^[2][3]

What Causes Air to Leak Into the Chest

The root cause of pneumothorax involves air escaping from the lung or entering through the chest wall and accumulating in the pleural space—the normally tiny gap between your lung and the inner chest wall. When air fills this space, it pushes against the lung and prevents it from expanding properly.^[1][2]

In primary spontaneous pneumothorax, small air-filled blisters called blebs form on the surface of the lung. When these blebs rupture, they release air into the pleural space. Scientists are still researching exactly why these blebs form, but they appear more commonly in certain body types and are linked to smoking habits.^[2][3]

Secondary spontaneous pneumothorax develops when existing lung diseases weaken the lung tissue. Conditions like emphysema can create larger air pockets called bullae within the lung. These diseased areas are fragile and can burst, allowing air to escape. Infections like tuberculosis or pneumonia can also damage lung tissue enough to cause air leaks.^[2][3]

Traumatic causes are more straightforward—physical damage to the chest wall or lung tissue creates an opening through which air can enter the pleural space. This might happen from broken ribs puncturing the lung, a knife wound penetrating the chest, or accidentally during medical procedures when needles or tubes are inserted near the lungs.^[3][2]

Risk Factors That Increase Your Chances

Smoking is one of the strongest risk factors for developing pneumothorax. People who smoke tobacco are much more likely to experience a collapsed lung compared to non-smokers. The risk applies to cigarette smoking and extends to cannabis use as well. Even vaping has been linked to increased pneumothorax risk.^[3][22]

Having a tall, thin body build appears to increase risk, particularly in young men. While researchers don’t fully understand why this physical characteristic matters, it’s consistently observed in people who develop primary spontaneous pneumothorax. This body type somehow makes the lungs more susceptible to developing those problematic blebs.^[3][5]

Existing lung diseases dramatically increase the likelihood of pneumothorax. Chronic obstructive pulmonary disease, asthma, cystic fibrosis, emphysema, tuberculosis, and lung cancer all weaken lung tissue in ways that make it easier for air to leak out. People with these conditions need to be particularly aware of pneumothorax symptoms.^[2][3]

Certain genetic conditions also raise risk. Marfan syndrome is a genetic disorder affecting connective tissue throughout the body, including in the lungs. People with this condition face higher pneumothorax risk. Similarly, about 1 in 10 people who experience pneumothorax have a family member who has also had one, suggesting genetic factors play a role in some cases.^[3][22]

Activities involving rapid pressure changes can trigger pneumothorax in susceptible individuals. Flying in airplanes, especially in unpressurized aircraft, and scuba diving both involve significant air pressure shifts that can stress the lungs. Inhaling drugs, particularly cocaine or marijuana, also increases risk through both the substances themselves and the forceful inhalation often involved.^[2][3]

Recognizing the Symptoms

The most common symptoms of pneumothorax are sudden, sharp chest pain and difficulty breathing. The chest pain typically appears on only one side—the side where the lung has collapsed. This pain often worsens when you try to take a deep breath, making breathing even more uncomfortable.^[1][2]

People experiencing pneumothorax often describe feeling short of breath, as though they cannot get enough air. This happens because the collapsed lung cannot expand properly to take in oxygen. The severity of breathlessness depends on how much of the lung has collapsed—a small collapse might cause only mild symptoms, while a large one can make breathing very difficult.^[2][5]

Your body may show other signs of respiratory distress. You might notice your breathing becomes faster than normal as your body tries to compensate for the reduced lung capacity. Your heart rate may also speed up. Some people develop a cough, though this is not always present.^[2][8]

In more severe cases, particularly with larger pneumothoraces or tension pneumothorax, additional symptoms can develop. Your skin, lips, or nails may take on a bluish tint—a condition called cyanosis—which indicates your blood is not getting enough oxygen. You might feel exhausted or dizzy. These more serious symptoms require immediate emergency care.^[2][5]

It’s worth noting that some people with small pneumothoraces may have minimal or even no symptoms at all. These cases might be discovered accidentally during chest X-rays performed for other reasons. However, even a small pneumothorax can potentially worsen, so medical evaluation is important once it’s detected.^[8]

Steps You Can Take to Prevent Pneumothorax

The single most effective preventive measure is to stop smoking or never start. Quitting smoking significantly reduces your risk of developing pneumothorax, particularly primary spontaneous pneumothorax. If you currently smoke, talk to your healthcare provider about smoking cessation programs and medications that can help you quit successfully.^[7][24]

If you have an existing lung condition that increases your pneumothorax risk, managing that condition well is crucial. Follow your treatment plan carefully, take prescribed medications as directed, and attend regular check-ups with your healthcare provider. Good disease management can help keep your lungs as healthy as possible and potentially reduce pneumothorax risk.^[2]

People with genetic conditions like Marfan syndrome should work closely with their healthcare team to monitor lung health. Regular medical follow-up allows for early detection of problems and appropriate interventions if needed.^[3]

If you’ve already experienced a pneumothorax, preventing recurrence becomes a priority. Unfortunately, pneumothorax tends to recur—after one episode, the risk of having another increases significantly. Your doctor may recommend certain interventions, possibly including surgery, to prevent future episodes. Following medical advice carefully after your first pneumothorax is essential.^[12][21]

Being cautious about activities that involve pressure changes can help protect susceptible individuals. If you have risk factors for pneumothorax, discuss with your doctor whether activities like scuba diving or flying in small aircraft are safe for you. Avoiding inhaled drugs is also important, as these significantly increase risk.^[2]

How Pneumothorax Changes Normal Body Function

To understand what happens during pneumothorax, it helps to know how breathing normally works. Your lungs sit inside your chest cavity, separated from the chest wall by a thin space called the pleural space. This space normally contains just a small amount of fluid that allows the lung to glide smoothly against the chest wall during breathing. The pressure in this space is slightly negative compared to the air pressure inside your lungs, which helps keep the lungs expanded.^[3][13]

When air enters the pleural space during pneumothorax, it disrupts this delicate pressure balance. The air takes up room in the pleural space and creates pressure against the outside of the lung. Because the lung is essentially an elastic structure, this external pressure causes it to deflate, much like air pressing on an inflated balloon would cause it to shrink.^[1][2]

The collapsed portion of lung cannot participate in gas exchange—the vital process where oxygen moves from air into your bloodstream and carbon dioxide moves from blood into air to be exhaled. When part of your lung cannot exchange gases, your body receives less oxygen than normal. This is why people with pneumothorax feel short of breath and may show signs of oxygen deficiency like bluish skin.^[2]

Your body tries to compensate for the reduced lung function. Your breathing rate increases to try to take in more oxygen with the remaining working lung tissue. Your heart rate speeds up to circulate the oxygen-poor blood faster. These compensatory mechanisms work reasonably well for small pneumothoraces but become overwhelmed when larger portions of lung collapse.^[8]

In the dangerous situation called tension pneumothorax, air continues entering the pleural space but becomes trapped and cannot escape. This creates a one-way valve effect where pressure builds with each breath. The mounting pressure can push the heart and major blood vessels toward the opposite side of the chest—a phenomenon called mediastinal shift. This pressure on the heart and blood vessels interferes with blood circulation, causing blood pressure to drop and potentially leading to shock, which can be fatal without immediate treatment.^[3][11]

The mechanical changes also affect the remaining healthy lung. Even though the lung on the opposite side is not directly affected, the mediastinal shift and altered chest mechanics can make it harder for that lung to expand fully. This compounds the breathing difficulties and oxygen shortage.^[3]

Over time, if a pneumothorax is left untreated, the persistent collapse can lead to scarring and permanent changes in the lung tissue. However, with prompt treatment, most pneumothoraces resolve completely, and the lung can return to normal function within several days to weeks.^[9][19]