What causes phlegm to flow from the nose to the throat?

The article was professionally consulted with Doctor CKII Nguyen Van Thai - Department of Medical Examination & Internal Medicine - Vinmec International General Hospital Da Nang.

Normally, phlegm from the nose will flow directly to the outside. However, in some cases, sputum discharge from the nose down the throat. Especially when the sputum is thick and has a bad smell, you should be careful. Because this can be a potential symptom of many respiratory diseases. Let's find out what is the cause of phlegm from the nose to the throat in this article.

Sputum from the nose to the throat is also known as postnasal drip. This condition is characterized by sputum discharge from the nasopharynx, through the nose, and down to the back of the throat.
In the early stages, most patients will not be able to recognize the characteristic symptoms of this condition. However, in some cases where the disease is serious, most patients feel a clear phenomenon of mucus backing up in the throat.
The discharge of phlegm from the nose to the throat is often accompanied by the following symptoms:
Cough a lot, especially at night. Halitosis. Sore throat. Feeling nauseous as the phlegm moves down to the stomach. There is a feeling of tightness in the throat.

There are many causes of phlegm discharge from the nose to the throat such as:
1.1. A deviated nasal septum A deviated septum is a condition in which the septum does not develop normally, it is deviated to one side. The cause may be due to trauma or the result of injury right in the nose area after birth.
This phenomenon will directly affect the patient's health. It increases the risk of respiratory diseases. In many cases, a deviated nasal septum prevents phlegm from flowing from the nose to the outside and it causes phlegm to flow from the nose to the throat.
1.2. Due to sinusitis The discharge of phlegm from the nose to the throat is said to be one of the common symptoms in patients with rhinosinusitis.
Caused by sputum containing bacteria and fungi that clog the sinus openings leading to inflammation and pus formation in the sinus cavities. Long-term accumulation will lead to pus overflowing down the throat. The accompanying symptoms can be seen as cough, sore throat, bad breath,...

1.3. Due to Allergic Rhinitis Allergic Rhinitis is a condition in which the membrane lining the inside of the nose becomes inflamed when a patient breathes in allergens such as pollen, pet dander, dust, etc. Patients often have symptoms of sneezing. This is the body's response to these allergens.
Patients will often have stuffy nose, runny nose. However, in some cases, when the disease turns into a chronic stage, the sputum from the nose can flow down the throat. Although this is not a dangerous disease, it causes many discomforts and directly affects the health and daily life of the patient.
1.4. Vasomotor rhinitis is also one of the causes of sputum discharge from the nose to the throat. This disease is characterized by a condition in which the parasympathetic nervous system in the nasal mucosa overreacts to external agents such as weather, bacteria, mold,...
Patient has rhinoconjunctivitis Vascular symptoms are similar to those of allergic rhinitis. However, patients have less itchy nose and less sneezing, instead, more severe stuffy and runny nose. In some cases, patients have less stuffy and runny nose, there will be sputum discharge from the nose to the throat.

1.5. Other causes In addition to the above diseases, sputum discharge from the nose to the throat can also be caused by other causes such as:
Cold weather Due to viral infections Due to colds, flu Due to sudden weather changes Sudden due to dry air Due to side effects of some drugs During pregnancy in women Due to frequent hot and spicy food The phenomenon of sputum discharge from the nose to the throat if the cause is not found and treated soon complications can arise very easily. The reason is because the sputum usually contains a lot of bacteria as well as pathogenic fungi. These agents can cause tonsillitis, pharyngitis, and even gastrointestinal ulcers if this sputum is swallowed. Therefore, when you notice this phenomenon, you should see a doctor so that the specialist can find out the cause, and then have the appropriate treatment.

In addition to following the treatment regimen of a specialist, people with a runny nose can apply some home methods to help reverse this situation:
Use a humidifier: If dry air irritates the lining of your sinuses, you can use a nebulizer to humidify the air, which is thought to help alleviate the irritation. Nasal irrigation: You can buy over-the-counter nasal rinses or sprays at pharmacies. Salt water will help push irritants out of the nose, and at the same time dilute and help soothe the lining of the nose.

Mix salt water mouthwash: you can make your own dilute salt water to gargle daily by adding half a teaspoon of salt to 200ml of warm water and stirring. When gargling, you should tilt your head back, so that the salt water can reach the throat. Steam with essential oils or herbs: you can steam by covering your head with a towel and bringing your face close to a pot of hot water, keeping a safe distance. You can use lavender or rosemary essential oils or herbs such as mint, chamomile, fresh ginger to steam.

Good care not only helps to reverse the discharge of phlegm from the nose to the throat, but it also helps prevent recurrent respiratory diseases. You should take the following care and prevention measures:
Drink enough water every day, because water helps to thin the phlegm. You can add a little honey to a glass of warm water to soothe your throat and improve discomfort. Always keep your body warm, especially when the weather changes seasons or when you catch a cold. If you have seasonal allergies, be proactive about getting allergy shots before the season arrives. Need to clean living space and working space regularly. Avoid things that can cause you an allergic reaction. Regularly wash pillowcases, duvet covers, and cushions. The phenomenon of sputum discharge from the nose to the throat is often caused by respiratory diseases, so patients need to pay attention, so they should go to the doctor soon to find out the cause and then have the appropriate treatment. It is necessary to combine treatment with home remedies, along with a regimen of care and prevention to avoid recurrence of the disease.

If you have a need for consultation and examination at the Hospitals of the National Health System, please book an appointment on the website for service.