Dyspnea is the medical term that describes shortness of breath. It is a complex symptom that’s experienced by people in many different ways. 

Some people describe the uncomfortable sensation as not being able to breathe fast or deeply enough. Some say it feels like they are running out of air even while resting, while others report the sensation of urgently needing to inhale again, even before an exhalation is complete. 

Some people even describe dyspnea as “tightness” in the chest, which creates the feeling of constriction and physical inability to draw a breath. And still others describe their dyspnea as a physical tiredness when breathing. This feeling of starving for oxygen is also known as “air hunger.”

More than 50 percent of people with advanced stage cancer, and between 50 and 75 percent of people with lung cancer, experience dyspnea. It becomes more common in the final six weeks of life for people with advanced stage cancer. One of the most distressing symptoms of advanced cancer, dyspnea has physical, psychological, social, and spiritual implications.  

Not a lot is known about the underlying causes of dyspnea. When a cause can be identified, doctors do all they can to treat it (for instance, removing fluid that has built up around the lungs) in order to alleviate its symptoms. Other treatment options can include respiratory care and drugs including opioids, benzodiazepines, and steroids. 

“In the end, doctors look for reversible causes to treat first. If symptoms persist or there isn’t a reversible cause, doctors use both drug therapy and non-pharmacologic therapies like oxygen, Reiki, and guided imagery,” says Laura Morrison, MD, a Yale Medicine palliative care doctor who is part of the Palliative Care Program at Smilow Cancer Hospital. Most people with dyspnea can find relief with this systematic approach to care.

“Most people don’t realize that being able to feel airflow, whether with oxygen or room air flowing through a nasal cannula in the nose or with a fan blowing on one’s face, is therapeutic in itself,” she says. “Studies have shown this airflow alone creates signals to the brain that can help one feel less short of breath.” 

It is not always possible to identify what is causing dyspnea, but some potential causes include the following:

• Anatomical problems directly related to the cancer, such as obstruction of the airway by a tumor or damage to the tissues and fluid surrounding the lungs
• New medical problems that may be related to the cancer, such as pneumonia, a blood clot in the lungs, and weakening or paralysis of the respiratory muscles
• Side effects of cancer treatments like chemotherapy or radiation therapy
• Chronic or new medical problems not related to the cancer, such as congestive heart failure and obstructive lung disease
• Electrolyte disturbances
• Anxiety

It’s important to try to understand what’s causing the dyspnea, as treating the underlying cause can bring relief.

Tests that help identify the cause include the following:

• Radiologic imaging, like a chest X-ray or CT scan, to examine whether there are any obstructions in your lungs and airways
• A blood test called a Complete Blood Count (CBC) to assess for anemia and electrolyte abnormalities
• A Maximal Inspiratory Pressure (MIP) test that checks the strength of your breathing muscles

If testing identifies an underlying cause for the dyspnea, treatment focuses on solving that problem. For example, if a tumor is blocking the airways, treatments like surgery, radiation therapy, chemotherapy, or cauterization (or laser ablation) might be recommended to physically remove the tumor. In other cases, advanced cancer can cause anemia and chest infections, which in turn cause dyspnea. Treatments for anemia and infection would include blood transfusion and antibiotics.

If there is no clear underlying cause, treatment for dyspnea focuses on relieving symptoms and improving quality of life. There are medications that can help, such as opioids to reduce pain, benzodiazepines to reduce anxiety, and steroids to reduce inflammation that may be recommended, depending on the severity of discomfort you’re experiencing.

Cognitive behavioral therapy can be helpful, as well as teaching new methods of breathing that can ease discomfort, including pursed lip breathing, relaxed body positioning for easiest breathing, and paced breathing. There are other potential options that can assist with breathing, spanning from nebulizer treatments to noninvasive positive pressure ventilation and high-flow oxygen. 

“Yale Medicine cancer physicians (medical oncologists) have training in symptom management to address symptoms like dyspnea,” says Dr. Morrison. “Palliative care specialists are also available to work with cancer physicians for basic and more complex symptom management.”