A subacute cough is a type of cough that persists for 3 to 8 weeks. It falls between an acute cough, which lasts less than 3 weeks, and a chronic cough, which lasts more than 8 weeks.

There are various causes for a subacute cough, including infections, viruses, asthma, and allergies.

A man coughing into a tissue to represent a subacute cough. -2Share on Pinterest
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Many things can cause a subacute cough, such as:

  • Post-infectious cough: Often, a subacute cough follows a respiratory infection such as the common cold, influenza, or bronchitis. It occurs as the airways remain irritated and inflamed even after the infection has resolved.
  • Asthma: Asthma can present as a cough variant, especially if the cough worsens at night or with exercise.
  • Postnasal drip: Conditions such as sinusitis or allergic rhinitis can lead to excess mucus production, which drips down the throat and triggers coughing.
  • Gastroesophageal reflux disease (GERD): Acid reflux can irritate the throat and airways, leading to a persistent cough.
  • Pertussis (whooping cough): A bacterial infection that can cause a prolonged cough in adults, even after initial symptoms subside.

Symptoms of a subacute cough last 3 to 8 weeks. There can be various symptoms, depending on the underlying cause.

General symptoms include:

  • Persistent cough: The primary symptom is a cough that lasts beyond the acute phase (more than 3 weeks) but has not yet become chronic (less than 8 weeks).
  • Coughing fits: Episodes of intense coughing that may disrupt daily activities or sleep or cause discomfort.

Different symptoms may occur depending on the underlying cause of the subacute cough, for example:

  • Post-infectious cough: This can cause a persistent tickling or scratchy sensation in the throat. It can also lead to residual sputum production, which is when a person continues to cough up some mucus or phlegm after an illness.
  • Asthma: Underlying asthma can cause a whistling sound when breathing, especially noticeable at night or with physical exertion. It can also cause shortness of breath, particularly during physical activities, along with a sensation of tightness or pressure in the chest.
  • Postnasal drip: This can cause a person to frequently need to clear the throat due to mucus dripping down from the nasal passages. People may also have a feeling of mucus buildup in the throat.
  • Gastroesophageal reflux disease (GERD): People with GERD may experience heartburn, which is a burning sensation in the chest or throat that often occurs after eating. They may also have sour or bitter-tasting acid backing up into the throat or mouth. GERD can also cause people to experience vocal changes, such as hoarseness or a raspy voice, particularly in the morning.
  • Pertussis (whooping cough): This can cause a person to emit a high-pitched “whoop” sound when they inhale after a coughing fit. These coughing fits can be severe enough to induce vomiting, and prolonged coughing episodes can cause fatigue.

The treatment depends on the underlying cause, which includes:

  • Post-infectious cough: Symptoms will typically resolve within 3 weeks, but a person can continue to use over-the-counter (OTC) cold and cough medication, such as pain relievers and decongestants, to relieve their symptoms. A person should contact a doctor if their symptoms continue for more than 3 weeks.
  • Asthma: A person will likely have to manage asthma over the long term using bronchodilators and inhaled corticosteroids via an inhaler. Breathing exercises, supplements, and lifestyle changes can also help.
  • Postnasal drip: Medical professionals treat this with decongestants, antihistamines, or nasal corticosteroids.
  • GERD: A person can treat GERD at home with diet and lifestyle modifications and OTC medications, such as antacids. Doctors can also help manage GERD with medications such as proton pump inhibitors or H2 blockers.

Most people’s outlook for a subacute cough is generally positive, as it often resolves on its own or with appropriate treatment. However, the duration and resolution depend on the underlying cause.

Regular follow-up with a healthcare professional ensures that they can correctly identify and manage the underlying cause.

Keeping track of symptoms can help in adjusting treatments as necessary. Avoiding smoking, allergens, and other irritants can aid in faster recovery and prevent recurrence.

For people experiencing a subacute cough with any of the following symptoms, it is important to seek medical evaluation:

These symptoms may indicate a more serious underlying condition requiring prompt medical attention.

Why do I have a cough that will not go away, but I am not sick?

Smoking or vaping can cause a chronic cough that persists even when a person is not sick. Environmental irritants such as dust, smoke, mold, or allergens can also cause a cough.

A persistent cough that does not seem related to an illness could be due to several other factors, such as postnasal drip, asthma, or GERD. It may also be a lingering effect of a past respiratory infection.

What is a subacute post-infectious cough?

A subacute post-infectious cough is a type of cough that persists for 3 to 8 weeks following a respiratory infection, such as a cold or bronchitis.

It occurs due to lingering inflammation or irritation in the airways after the infection resolves.

When should I be worried about a cough?

People need to be concerned about a cough if it lasts longer than 8 weeks, is accompanied by symptoms such as high fever, significant weight loss, coughing up blood, severe shortness of breath, chest pain, or if it interferes significantly with their daily life.

In these cases, individuals need to seek medical evaluation to rule out more serious conditions.

A subacute cough, lasting between 3 to 8 weeks, often indicates a lingering or underlying condition such as post-infectious inflammation, asthma, postnasal drip, gastroesophageal reflux disease (GERD), or pertussis.

Proper evaluation and targeted treatment can lead to resolution, while ongoing monitoring ensures that doctors can address any complications or persistent symptoms promptly.