The sensation of choking on phlegm while asleep can be unsettling, but actual choking is uncommon. Phlegm is thick mucus produced by the respiratory system, often associated with illness or inflammation. Despite the alarming feeling of excess phlegm, the body has protective mechanisms to prevent airway obstruction during sleep.
The Body’s Natural Defenses Against Choking
The body has defense mechanisms to protect the respiratory tract from foreign material, including phlegm. A key structure is the epiglottis, a leaf-shaped flap of cartilage at the top of the larynx (voice box). During swallowing, the epiglottis automatically folds backward to cover the larynx opening, diverting food and liquids, including mucus, into the esophagus and away from the trachea and lungs.
Even during sleep, involuntary reflexes remain active to safeguard the airway. The cough reflex forcefully expels foreign bodies and secretions from the respiratory tract. While cough sensitivity is reduced during sleep compared to wakefulness, this reflex is not entirely suppressed, especially in cases of significant irritation.
Similarly, the swallow reflex clears saliva and functions involuntarily during sleep, though less frequently than when awake. These coordinated actions of the epiglottis, cough reflex, and swallow reflex prevent phlegm from entering the lungs, even when mucus production is increased. The mucociliary escalator, a system of cilia and mucus lining the airways, continuously moves trapped particles upwards towards the pharynx, where they can be swallowed.
Why You Might Experience Excessive Phlegm
Several conditions and environmental factors can lead to increased phlegm production, contributing to the sensation of choking or difficulty breathing at night. Post-nasal drip is a common cause, where mucus from the nose drips down the back of the throat, especially when lying flat, triggering a cough reflex. This can be a symptom of allergies, colds, or sinus infections.
Acid reflux (GERD) can also cause excessive phlegm. Stomach acid can flow back into the esophagus when a person lies down, irritating the throat and leading to coughing and increased mucus. Asthma symptoms, including airway inflammation and wheezing, often worsen at night due to natural changes in hormone levels and lung function, which can also increase phlegm.
Environmental irritants in the bedroom, such as dust mites, pet dander, or mold, can exacerbate coughing and phlegm production, particularly in individuals with sensitivities or asthma. Dry air can also irritate the airways, prompting the body to produce more mucus as a protective response.
When to Be Concerned and How to Manage Phlegm
Managing excessive phlegm often involves strategies to improve comfort and reduce the choking sensation. Staying well-hydrated by drinking plenty of fluids throughout the day helps to thin mucus, making it easier to clear from the airways. Using a humidifier in the bedroom can add moisture to the air, soothing the throat and potentially reducing coughing, with an optimal humidity level between 40-50 percent.
Elevating the head during sleep by using extra pillows or a wedge can help reduce post-nasal drip and manage acid reflux, preventing mucus from pooling in the throat. Avoiding known allergens and irritants in the sleeping environment, such as regularly washing bedding and vacuuming, can also minimize phlegm production. For temporary relief, a spoonful of honey before bed may soothe the throat and calm the cough reflex.
While these measures can provide relief, certain symptoms warrant medical attention. If you experience persistent shortness of breath, chest pain, fever, or notice bloody phlegm, seek medical advice. Severe difficulty swallowing, chronic phlegm production without an obvious cause, or if the sensation of choking is disruptive or causes panic also warrant a consultation with a healthcare provider.