Everyone has had a cough at some point or another in their lives, as a cough is a common symptom of many different types of illnesses and medical conditions. Coughs can be nagging, disruptive, and even painful, but exactly why do we cough and what are the different types and causes of coughs?

Exactly Why Do We Cough?

The cough reflex is often stimulated by inflammation or irritation from infections or allergies. We cough so that we can expel things from our airways that don’t belong there, including inhaled pollutants, food particles, excess mucus, allergens, cigarette smoke, strong perfumes, cold air, or other substances that irritate the lungs.

While we cough in order to expel foreign bodies from our lungs, there are several different types and causes of coughs.

What are the different types and causes of coughs?

The four primary types of coughs include dry cough, wet cough, croup cough, and paroxysmal cough. Each of these types of coughs is caused by different irritants or illnesses.

Dry Cough

One type of commonly experienced cough is the dry cough. Dry coughs, or unproductive coughs, are so named because they do not cause a person to cough up excess mucus or phlegm. In some cases, dry coughs might not appear to have an obvious cause, and they might start as an irritating or tickling sensation at the back of your throat.

Dry coughs can be hard to suppress. As a result, it is common for people experiencing a dry cough to cough for extended periods of time. Many people may experience a persistent dry cough after they start recovering from upper respiratory infections, the common cold, or the flu.

While wet coughs, which produce excess mucus or phlegm from the airways, typically resolve after congestion has cleared, dry coughs may linger for an extended period of time even after the rest of your symptoms have gone away.

Common causes of dry cough include:

• Cold
• Croup
• Flu
• Laryngitis
• Sinusitis
• Allergies
• The use of certain medications, such as lisinopril
• Sore throat
• Exposure to irritants in the air, including smoke, pollution, or dust
• Tonsillitis
• Asthma
• Acid reflux or gastroesophageal reflux disease (GERD)

Dry coughs have recently received more attention as a result of the COVID-19 pandemic, as a dry cough is one of the most common and well-known symptoms associated with this highly contagious disease.

Experiencing a dry cough does not mean that you have COVID-19, but there are other symptoms to look out for that commonly occur with the illness, including:

• Fever
• Chills
• Fatigue
• Difficulty breathing
• Shortness of breath
• Loss of taste or smell
• Sore throat
• Muscle or body aches
• Diarrhea
• Nausea or vomiting
• Headache
• Congestion or runny nose

Wet Cough

A wet cough is a cough that produces excess mucus or phlegm. Wet coughs are commonly associated with different types of illnesses, and they can cause the chest to feel heavy, tight, or tired.

Illnesses known to cause a wet cough include:

• Common cold
• Asthma
• Pneumonia
• Emphysema
• Chronic bronchitis
• Flu
• Chronic obstructive pulmonary disease (COPD)
• Acute bronchitis

A wet cough is typically triggered by a feeling of saliva, phlegm, or mucus being built up in the throat or chest. A wet cough loosens the mucus, phlegm, or saliva caught in the airways and brings the substance into the mouth, allowing it to be spit out.

Excess mucus or phlegm in the respiratory system, including the lungs and airways, makes it difficult to breathe properly. The body naturally produces mucus that lines all of the parts of the respiratory system, including the lungs, nose, throat, airways, and mouth.

However, illness or allergies can cause you to produce too much mucus or produce mucus that is too thick to cough up easily, which can lead to congestion. It is common to experience symptoms like postnasal drip, runny nose, or fatigue alongside a wet cough.

Wet coughs are categorized as acute or chronic depending on how long they last and the medical issue contributing to the cough. Acute wet coughs are typically experienced for less than three weeks as a result of a short-lived illness, such as a cold or flu. A chronic wet cough is a cough that lasts three to four weeks or longer in children or eight weeks or longer in adults. Chronic wet coughs can be attributed to long-term respiratory issues that may serve as triggers.

Croup Cough

Croup is an infection of the upper airway that most commonly occurs in younger children, particularly those between six months and three years of age. This illness causes a distinctive cough that sounds like a barking seal due to irritation and swelling of the passages of the upper airway.

Besides the distinctive croup cough that sounds like a barking seal, croup commonly causes the following symptoms:

• Noisy or labored breathing
• Rapid breathing
• Swelling around the larynx (voice box), bronchial tubes, and windpipe (trachea)
• Hoarse voice
• Fever
• A high-pitched whistling sound that occurs during inhalation

Croup is a short-lived but intense illness that typically lasts about three to five days. Most children experience the worst symptoms at night. While the condition can be scary for parents and children, it is usually not severe. However, there are some severe cases of croup.

Be sure to seek medical attention for your child if any of the following issues occur:

• Your child starts making noisy, high-pitched sounds while inhaling and exhaling
• Your child makes high-pitched breathing sounds when not crying or agitated
• Symptoms persist for more than three to five days
• Your child seems fatigued and listless or anxious and agitated
• Your child begins drooling or has difficulty swallowing
• Your child is breathing at a faster rate than normal
• Your child struggles to breathe
• Your child develops grayish or blue skin around the nose, nail beds, or mouth
  

Paroxysmal Cough

One severe type of cough is referred to as a paroxysmal cough. This exhausting cough is typified by violent coughing fits that cannot be controlled, making it difficult to take in enough oxygen. Paroxysmal coughs are painful and may cause symptoms like vomiting when not enough oxygen is received.

There are several medical conditions that are commonly associated with paroxysmal coughs, including:

• COPD
• Tuberculosis
• Choking
• Asthma
• Whooping cough (pertussis)
• Pneumonia

When observed in children, paroxysmal cough is most commonly caused by a highly contagious bacterial infection known as whooping cough, or pertussis. This infection of the respiratory tract is marked by a distinctive, painful cough that causes the patient to sharply intake air, causing a high-pitched “whoop” sound. The sound is made by the complete release of air from the lungs during the coughing fit, which causes the patient to need to take a large fast breath after they finish coughing.

Whooping cough can be very dangerous, but it is preventable, as there is a vaccine for it. Babies can start to get vaccinated beginning at two months of age. As a result, whooping cough is most commonly observed in babies who are too young to be vaccinated as well as adults and older children who lose their immunity over time. Whooping cough can be fatal and is especially dangerous for infants, so people who come into contact with very young infants should be vaccinated.

The symptoms of whooping cough typically begin within seven to ten days of infection and often start out as mild. Early symptoms include:

• Cough
• Runny nose
• Nasal congestion
• Fever
• Red, watery eyes

Symptoms of whooping cough tend to progress after a period of one to two weeks as a result of mucus accumulation in the airways. The buildup of mucus makes it difficult to breathe and causes uncontrollable coughing fits, which can result in extreme fatigue, vomiting, or difficulty breathing. Infants may not cough at all and instead may simply struggle to breathe or even stop breathing, which is an emergency.

Summary

A cough is the body’s way of expelling foreign substances, allergens, or germs from the airways, helping to prevent infection and ensure that we are able to breathe easily. There are four primary types of coughs, including dry cough, wet cough, croup cough, and paroxysmal cough, each of which has different causes and slightly different symptoms.