Green Phlegm With a Sore Throat: Causes & What to Do

Key takeaways:

• Sore throats are most commonly caused by viruses but can also result from bacteria, allergies, or environmental factors.
• Green phlegm usually indicates infection, but allergies or other conditions can also be responsible in some cases.
• See a doctor if symptoms persist beyond 48 hours, worsen, or are accompanied by severe signs like fever or difficulty breathing.

Sore throat is one of the most common symptoms for which patients are seen. It is a frustrating and sometimes painful symptom. Usually, a sore throat is due to a respiratory virus. There are cases when a bacterial infection causes a sore throat. There are times when a sore throat is not caused by an infection. Allergies, acid reflux, throat dryness, and even second-hand smoke exposure cause a sore throat.

What green phlegm and sore throat means

Green phlegm (or sputum) typically indicates infection of some kind. Phlegm is produced by irritated airway cells. These cells live in our throat, airway passages, and lungs. The infection can be viral or bacterial. If you are coughing up a lot of green phlegm and running fevers, you may have bacterial pneumonia.

Cause of a sore throat with green phlegm

A sore throat with green phlegm can have multiple causes. A viral infection of the respiratory tract is one of the most common.

Viral respiratory infection

Viral pharyngitis is an infection of the lining of our throat. The same viruses responsible for colds are often behind viral pharyngitis. You may also notice a cough, runny nose, or congestion.

Bacterial infection

Around 25-35% of the time, sore throat is due to bacterial infection. Strep throat is a common bacterial infection causing sore throat, but there are others. Additional symptoms include a cough, fever, and tender lumps in your neck (swollen lymph nodes).

Pneumonia

Pneumonia is an infection of the lungs. It is caused by bacteria or viruses. Sometimes what begins as an infection of the throat causes pneumonia. Typically pneumonia due to bacterial infection causes green phlegm. A virus could also cause this, however.

Allergies

Sometimes a sore throat is due to an allergic reaction. Allergic irritation of the nose leads to runny nose or congestion, sneezing, and mucus dripping down the throat from the nose. This is called post-nasal drip. It causes a sore or scratchy throat.

This mucus that drips down the throat can also cause us to cough. While the mucus in allergic conditions is usually clear, this is not always the case. It can be difficult to assess mucus color.

Other causes of green phlegm with a sore throat based on another symptom, condition, or situation

At times, the presence of additional symptoms can help identify the cause.

Green phlegm with a sore throat, but no fever

An allergic cause of sore throat with green phlegm is one possibility. Allergies do not usually cause fevers. Other symptoms may include runny nose or congestion, sneezing, irritated eyes, and a cough.

Green phlegm with a sore throat, but no cough

This too may point to an allergic cause of the symptoms. The allergic reaction in our nose and upper airways causes mucus (phlegm) to form. It may not always cause a cough though.

Green phlegm with a sore throat and headache

Headache can be a symptom of the virus or bacteria causing the illness. It can also be due to dehydration. A sore throat can understandably lead us not to want to eat or drink. If this leads to dehydration, headaches can result.

Green phlegm with a sore throat and body aches

This collection of symptoms would point to a viral or bacterial infection. It can also indicate pneumonia.

Green phlegm with a sore throat and no voice

This too may indicate bacterial or viral infection of the throat. If the infection spreads to the larynx (voice box), it can affect the voice.

At-home remedies for relieving a sore throat and green phlegm

There are options for treatment of sore throat to help you feel better. The green phlegm is a result of the irritation caused by your condition. When the condition improves, the phlegm should go away.

Throat lozenges and sprays

Many lozenges and sprays are available for sore throat. You should look for a product containing one of these four ingredients: menthol, dyclonine, benzocaine, or hexylresorcinol. All of these have some local anesthetic properties. This means they will numb the irritated tissue in your throat.

There is no evidence that any one of these is better than the other. Lozenges may last longer than sprays, and be easier to take.

Warm or cold fluid intake

Cold fluid intake, such as sucking on ice chips or popsicles, can relieve sore throat pain. Cold fluid has a numbing effect on tissue. Further, this is an effective way to rehydrate yourself.

You may prefer warm fluid such as tea with honey or soup. This is also an effective method. Choose the approach that you prefer. One is not better than the other.

Pain medications

Over-the-counter pain medications are effective treatments for sore throats. Acetaminophen or ibuprofen are popular choices. Research shows that ibuprofen might be more effective.

You should choose a lower dose at first (200 mg for ibuprofen, and 325 mg for acetaminophen). You can always increase it later on. If you have stomach ulcers or kidney problems, you should avoid ibuprofen.

Environmental changes

Humidifying the air can help prevent your throat from drying out, which may worsen symptoms. This can be achieved with an air humidifier or by running a hot shower in a closed room for a few minutes. Avoiding second-hand smoke exposure is also important to avoid further irritating your throat.

When you should see a doctor for a sore throat with green phlegm

There are times when a sore throat with green phlegm should prompt you to see a doctor.

You should see a doctor if:

• You have a fever (temperature greater than 100.4 degrees Fahrenheit).
• Your symptoms don’t improve after 48 hours.
• Your symptoms are severe.
• You are having trouble eating or drinking.

You should go to the emergency room if:

• You have trouble breathing.
• If you are drooling because you can’t swallow your saliva (spit).
• Your neck or tongue is swollen.
• You can’t open your mouth or move your neck.

Questions to ask your doctor about a sore throat and green phlegm

• What is causing these symptoms?
• Can I do anything at home for them?
• Am I contagious?
• How long will this last?

How a doctor can help treat a sore throat with green phlegm

Treating a sore throat depends on the cause.

Antibiotics

A doctor will prescribe antibiotics if your symptoms are caused by a bacterial infection or bacterial pneumonia. It is important to take them exactly as prescribed. If you stop them early, your infection can return and be worse than before.

Home remedies

The home remedies discussed above may be the only treatment you need. This is especially true for viral infections. If your condition is due to allergies, your doctor may recommend over-the-counter or prescription medications for this.

Frequently asked questions: sore throat with green phlegm

It is normal to have questions about a sore throat with green phlegm. Please ask your doctor questions until you understand what is happening.

Should you consider yourself contagious if you have a sore throat and green phlegm?

It is always safer to assume you are contagious, but you should also speak to your doctor. Conditions due to allergies are not considered contagious.

Is a sore throat and green phlegm a sign of COVID?

The virus responsible for COVID-19 is one of the leading viral causes of sore throat. The COVID-19 virus can irritate the throat and upper airway passages, leading to phlegm production.

Closing thoughts

It is okay to monitor your sore throat and green phlegm at home for a day or two. If you have symptoms longer than two days or begin to run fevers, please call your doctor.

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. Pallabi Sanyal-Dey, MD.

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