Post-COVID Cough With Phlegm: Treatments & When It’s Serious

Key takeaways:

• A persistent cough with phlegm can occur after a COVID-19 infection and may last several weeks.
• A cough with phlegm that persists for more than eight weeks after a COVID-19 infection falls under the umbrella of long COVID and may benefit from alternative treatment options.
• A post-infectious cough with fever, chest pain, or shortness of breath should be evaluated promptly by a healthcare provider.

As if suffering through the symptoms of COVID-19 is not punishment enough, realizing that you have a persistent cough with phlegm after the infection clears is the cherry on top. This lingering cough can be caused by the body’s continued recovery from the viral infection, inflammation in the respiratory tract, or, sometimes, damage to the lungs due to the infection.

While some degree of post-COVID coughing may persist for weeks, it is important to differentiate between a normal post-viral symptom and a sign that something more serious is developing. In this article, we will discuss how long a post-COVID cough can last and what you can do to get relief. We will also cover instances when this cough is no longer considered normal and prompts medical attention.

Is it normal to have a cough with phlegm after COVID?

Having a cough with phlegm after a COVID-19 infection is both normal and common. Any type of respiratory infection—COVID-19 or otherwise—can cause significant inflammation and irritation in the lungs that may trigger a cough response. Inflammation can take several weeks to resolve, and a cough tends to hang around until the inflammation is gone.

Duration of a post-COVID cough with phlegm

A cough with phlegm may persist for weeks after the other symptoms of the virus have resolved. This condition is known as “post-viral cough,” and it can occur due to residual inflammation in the airways.

According to studies done on patients experiencing symptoms after a COVID-19 infection has resolved, the post-COVID cough has been categorized into three categories:

• Acute cough lasts three weeks or less.
• Subacute cough lasts three to eight weeks.
• Chronic cough, a symptom of long COVID, lasts for more than eight weeks.

Other symptoms associated with a post-COVID cough with phlegm

A cough with phlegm after COVID-19 can occur alongside other symptoms, which may help determine whether this is a “normal” post-infectious cough, a sign of a secondary infection, or chronic damage to the lungs.

Shortness of breath

Shortness of breath is a common symptom of an acute COVID-19 infection, but it can also occur after the infection has cleared. If the infection has caused significant inflammation in the lungs or damage to lung tissue, you may experience shortness of breath in addition to a post-viral cough with phlegm. Shortness of breath should always be evaluated by a healthcare provider.

Fatigue

Persistent tiredness or fatigue is another common symptom of long COVID. Fatigue can be exacerbated by a cough and difficulty sleeping due to throat irritation or mucus buildup. Many patients report that fatigue can persist for several weeks to months, even after the acute infectious phase has passed.

Fever

COVID-19 infections can lead to secondary lung infections such as pneumonia, particularly in patients with weakened immune systems. COVID-19 can also cause long-term lung damage that leaves you prone to infections. If you are experiencing a new onset of fever with shortness of breath, cough with phlegm, or wheezing after your COVID-19 infection has resolved, a secondary infection should be considered.

How to get relief from a post-COVID cough with phlegm at home

If you are experiencing a cough with phlegm after a COVID-19 infection, you might want to run to your doctor for prescription medication. Because a post-COVID cough with phlegm is a common symptom, you may want to first try home remedies.

Over-the-counter medications

Over-the-counter expectorants like guaifenesin (Mucinex) work by thinning the mucus and making it easier to cough up. Cough suppressants such as dextromethorphan (Robitussin) can reduce the urge to cough by minimizing the cough reflex. Cough drops can also be a helpful tool to power through this period of post-infectious coughing.

Humidifier

Dry air can aggravate a cough. A humidifier, which adds moisture to the air, can soothe the airways, making it easier to breathe and helping to loosen mucus. A warm steam shower may also help to loosen phlegm.

Honey

Honey is a widely used home remedy for coughs that has been used for ages. It coats the throat to reduce irritation and has antimicrobial properties, as well. Much research has been done, and tons of emerging evidence supports honey’s use for the relief of coughs.

When you should see a doctor about coughing up phlegm after COVID

While a post-COVID cough with phlegm is likely to resolve on its own after what may feel like many, many weeks, there are times when you should consult a doctor.

You should see a doctor if:

Consult your doctor if one or more of the following occurs:

• Your cough lasts more than eight weeks.
• You experience wheezing or chest tightness.
• You have a new-onset fever after your COVID-19 infection resolves.

You should go to the emergency room if:

Seek immediate medical attention if:

• You are having trouble breathing.
• You are experiencing significant or sudden sharp chest pain.
• Your lips or face turn blue, indicating a lack of oxygen.
• You notice a significant amount of blood in your phlegm.

Questions to ask your doctor about coughing up phlegm after COVID

• I am no longer testing positive for COVID-19, so why am I still coughing?
• How long should I expect this cough with phlegm to last?
• Does my persistent cough with phlegm mean that I have lung damage from the virus?
• Do I need an antibiotic or some kind of prescription medication for my symptoms?

Diagnosing coughing up phlegm after COVID

If your only symptom is a persistent cough with phlegm, your doctor may not perform any additional diagnostic studies, as this is a common symptom after a COVID-19 infection. If you are experiencing a fever, shortness of breath, or sharp chest pain, your healthcare provider may order an X-ray or CT scan of your chest. They may also order a sputum culture and pulmonary function tests.

How a doctor can help treat coughing up phlegm after COVID

If your post-COVID cough requires medical intervention, several available treatment options may help alleviate symptoms.

Medications

Antibiotics are not necessary unless you develop a secondary bacterial infection. However, your healthcare provider may prescribe other medications to minimize symptoms. Oral and inhaled corticosteroids can help reduce inflammation that causes a cough in patients with post-acute and long COVID symptoms. Your doctor may also prescribe dextromethorphan, gabapentin, montelukast, or lidocaine.

Physiotherapy

Physiotherapy is one of the main tools patients use to manage chronic lung complications of COVID-19. You may benefit from breathing exercises or aerobic exercises to improve lung function.

Frequently asked questions: post-COVID cough with phlegm

Experiencing a prolonged cough with phlegm after the resolution of COVID-19 can leave you with more questions than answers. Here are some of the most frequently asked questions related to this symptom.

What if you’re coughing up yellow phlegm after COVID?

When you have some type of irritant in the lungs, white blood cells rush to the area to try and rid the respiratory tract of anything foreign. This response is triggered by viral infections, bacterial infections, and general inflammation of the lungs.

As the white blood cells die, they release an enzyme that causes the phlegm to turn yellow or green in color. If you are coughing up yellow phlegm after COVID-19, simply know that your body is actively continuing to heal itself after the infection.

What if you’re coughing up white phlegm after COVID?

White phlegm is often a sign of inflammation rather than infection. It can be common in viral illnesses and in conditions that cause inflammation in the lungs. If this is your only symptom and you are otherwise feeling fine, white phlegm likely indicates that the body is still healing from the virus.

Final thoughts: Is this cough here to stay?

Although we are several years beyond the initial emergence of COVID-19, a lot about the virus remains unknown. One thing we do know is that it is quite common to experience coughing with phlegm that can last for weeks or even months after the resolution of the acute infection.

While it can be uncomfortable, persistent coughing and phlegm production usually improve over time as the lungs heal and the inflammation improves. However, if symptoms worsen or persist beyond eight weeks, or you develop additional symptoms such as fever, chest pain, or shortness of breath, please see a healthcare provider.

General Medicine follows a strict editorial process, including using real experts to write our articles, vetted primary sources, fact-checking, a secondary medical review, and updates as necessary. This article was medically reviewed and fact checked by Dr. Marjorie Bravard, MD.

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