Coughing And Sleep: Why We Don't Cough During Slumber

Coughing and sleep are vital functions, and the effects of coughing on sleep and vice versa are important for several reasons. Sleep disruption due to coughing is a common issue for patients with a chronic cough, and they may seek medical attention for it. However, it is uncommon for healthy people to cough at night. Coughing is suppressed during sleep, and the biological mechanisms behind this are not yet fully understood.

We can cough in our sleep, but only during light sleep

It is possible to cough in your sleep, but only during light sleep. During deep sleep, the body limits certain muscle movements, and you will not cough or sneeze. However, if your body needs to cough to remove an obstruction, it will move from deep to light sleep, resulting in less restful sleep and leaving you more tired the next day.

When you cough or sneeze, your body enters a brief wakeful state, and you may not remember being awake. This is because, during sleep, nerve transmission down the spinal cord is inhibited. However, the body will wake up just enough to cough or sneeze, and then quickly fall back asleep. This is why you might not remember coughing or sneezing during your sleep.

Coughing is a protective reflex, and your respiratory tract will wake you up if it is irritated enough. This is why people with respiratory issues might cough more at night. Additionally, there is less exposure to tussive stimuli at night, and cough reflex sensitivity is decreased.

Habit cough, a type of functional respiratory disorder, is characterised by a persistent involuntary cough that is absent during sleep. This condition is typically seen in children and is believed to be caused by psychological or emotional stressors.

Coughing is suppressed during REM sleep

REM sleep is important for several reasons, including memory consolidation, emotional processing, brain development, and dreaming. It is also the stage of sleep in which most dreams occur. While it was previously hypothesised that the loss of muscle tone during REM sleep was a protective measure to prevent people from acting out their dreams, this theory is now being questioned due to the discovery that dreams can also occur during non-REM sleep.

Coughing during sleep is possible, but it usually only occurs during light sleep. People with certain conditions, such as chronic cough, obstructive sleep apnea, or gastroesophageal reflux, may experience coughing and sleep disruption. Studies have shown that the cough reflex is suppressed during sleep, particularly during REM sleep when compared to slow-wave sleep. This may be due to reduced exposure to tussive stimuli and decreased cough reflex sensitivity at night.

The suppression of coughing during sleep is not yet fully understood, but it is believed to be related to the body's natural decrease in cough sensitivity during sleep. However, those with acute, subacute, or chronic daytime cough may experience a disruption in their sleep due to a loss of this natural decrease in cough sensitivity.

Habit cough is a functional disorder characterised by coughing fits during the day, but not at night

The age distribution of patients with habit cough ranges from 4 years to late adolescence, with 85% of cases occurring between 8 and 14 years of age. Similar coughing in adults is much less common and poorly characterised. Habit cough in adults has generally not been recognised, and a behavioural component has not been considered in cases of idiopathic chronic cough. However, recent reports suggest that a small number of adults with chronic cough may also suffer from habit cough.

Habit cough is often misdiagnosed as asthma, and patients are subjected to extensive medical evaluation and treatment. However, pharmacological treatment is ineffective for habit cough. A simple behavioural approach called suggestion therapy has been applied with success by many physicians.

Coughing at night can be caused by post-nasal drip

Coughing is one of the body's vital functions, and it is uncommon for healthy people to cough at night. However, coughing at night can be caused by post-nasal drip, which is the drainage of mucus from your nose or sinuses into your pharynx, or throat.

Post-nasal drip is a common diagnosis with a variety of causes, including allergies, viral infections (such as the common cold), sinus infections, irritants in the air (such as fumes or dust), and even certain medications. When your body produces more mucus than usual or it is thicker than normal, it becomes more noticeable. This excess mucus can come out of the nostrils, resulting in a runny nose, or it can run down the back of your nose to your throat, causing post-nasal drip.

Post-nasal drip can lead to a nagging cough that often gets worse at night. The mucus can irritate the throat, triggering a cough. In fact, post-nasal drip is one of the most common causes of a persistent cough. The excess mucus can also cause a sore or irritated throat, and in some cases, it may lead to inflammation and swelling of the tonsils and other tissues in the throat.

If you are experiencing coughing at night due to post-nasal drip, there are several treatments you can consider. Home remedies include using a humidifier or inhaling steam, staying well-hydrated to thin the mucus, propping yourself up with pillows while sleeping to prevent mucus from collecting in your throat, and nasal irrigation. Over-the-counter medications such as oral or nasal decongestants, antihistamines, and mucus-thinning medications can also help. If these options are ineffective, prescription treatments such as nasal steroid sprays or antibiotics (in the case of bacterial infections) may be recommended by a doctor.

Heart failure can cause a dry cough at night

Coughing is a natural reflex that helps clear the lungs and throat of mucus, dust, and other pollutants. While coughing is a common occurrence, it is less frequent at night due to reduced exposure to tussive stimuli and decreased cough reflex sensitivity. Sleep also suppresses coughing, although the biological mechanisms behind this are not yet fully understood.

However, coughing at night can be a symptom of various medical conditions, including dental issues and lung or respiratory problems. One condition that can cause night-time coughing is heart failure, specifically congestive heart failure (CHF). CHF occurs when the heart cannot pump enough blood to meet the body's demands, resulting in fatigue, shortness of breath, and wheezing or chronic coughing. The inability of the heart to pump blood effectively leads to blood and fluid backup in the lungs and legs, causing pulmonary congestion and leakage of fluid into the air sacs (alveoli). This fluid buildup in the lungs triggers a persistent cough, known as a cardiac cough or cardiac asthma.

The cardiac cough associated with heart failure tends to worsen at night and can be dry or wet. A dry cough is a persistent cough with no mucus production, while a wet cough is often described as whistling and accompanied by mucus. In addition to coughing, other symptoms of cardiac asthma include pink or white phlegm, shortness of breath, rapid and shallow breathing, difficulty breathing when lying down, and crackling sounds in the lungs.

If you are experiencing a persistent dry cough at night, it is important to consult a healthcare professional, especially if you have any risk factors or symptoms of heart failure. Early diagnosis and treatment of heart failure are crucial to prevent progression to the advanced stages of the disease.

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