What is Post Nasal Drip?
Post nasal drip describes excess abnormal mucus draining from the back of the nose into the throat. It is generally a symptom of other conditions such as infections, allergies or nasal deformities.
Glands in the nose produce mucus continuously, on average up to two litres every day. This mucus helps clean and moisten the membranes in the nose, fights infection and humidifies the air we breathe. It also traps any foreign bodies, such as dust, which we inhale and clears them away. (1)
The mucus is usually swallowed without being noticed. However, when it is felt dripping into the throat, it is classed as post nasal drip. It can also be felt as a buildup of mucus in the throat.
There are conditions which cause a change to the volume and texture of the mucus produced in the nose. Some can make it more watery and others make it thicker. There are also conditions which affect the way the mucus drains from the nose.
Thin Nasal Secretion
There are several factors which can play a part in thinning nasal secretions leading to post nasal drip.
Viruses, such as those associated with flu or the common cold and allergic reactions, increase mucus production.
Other things that contribute are hot spicy foods, cold temperatures, bright lights, pregnancy and hormonal changes.
Certain medications, including those for high blood pressure or birth control, affect the viscosity and production of mucus.
Some genetic abnormalities in the structure of the nose, particularly concerning the cartilage which separates the nostrils (septum), also contribute. These conditions are called a deviated or irregular nasal septum. (2, 3)
Thick Nasal Secretion
Mucus which becomes thickened can be more difficult for the nose to drain and for the throat to clear.
Factors affecting this include sinus or nasal infections, allergic reactions and environmental irritants like smoke and pollution.
Central heating and air conditioning dry the air in our homes and workplaces. As a result the nose is not provided with enough humidity, and secretions become thicker.
When the nasal discharge appears yellow or green in color, as well as being thicker, it is likely caused by a bacterial infection.
Secretions from one nasal passage, particularly in children, could indicate a blockage in the nasal passage. There may be a part of a toy, some paper or a bit of candy stuck in the nostril. (4, 5)
There are several common symptoms associated with post nasal drip. These include:
When an accumulation of thicker nasal secretion builds up the throat there may be an urge to cough to clear it. Coughing can also be the result of thinner secretions dripping into the throat. This causes a tickling sensation, leading to a cough.
This symptom can often be worse at night or when first waking in the morning. (6)
Post nasal drip might lead to a person swallowing more often. They also might feel the need to clear the throat. (7)
Production of excess mucus building up in the stomach might cause a feeling of nausea, eventually leading to vomiting. (8)
Constant throat clearing and coughing associated with this condition can lead to the throat becoming irritated and sore. (9)
Infections in the respiratory tract, which can be a cause of post nasal drip, can result in people experiencing bad breath. (10)
There are underlying conditions which can contribute to post nasal drip, these include:
The sinuses consist of air filled cavities located in the cheeks, behind the nose and in the forehead. They have small openings into the nose which allows for the drainage of fluid.
Colds, flu or allergies can lead to the sinuses filling with fluid and becoming infected. When this happens, particularly if due to bacteria, post nasal drip might be experienced.
If a blockage in the sinuses persists and becomes chronic, polyps or growths might develop in the nose. Often, when polyps are present, post nasal drip will be constant and persistent. (11)
Enlarged Nasal Turbinates
Nasal turbinates are structures made of bone and tissue situated on the inside of the side walls of the nose. Their primary function is to humidify (moisturize) air and warm it when it enters the nose as we breathe in.
When these are enlarged airflow through the nose is restricted and drainage of nasal fluid is impaired. The result is post nasal drip, and also more frequently, risk of bacterial infection. (12, 13)
Certain medical conditions contribute toward an increased production of mucus leading to post nasal drip. These include pregnancy, menopause, hypothyroidism, kidney disease, diabetes and colitis. (14)
Emotional Post Nasal Drip
Some people might perceive that they suffer from post nasal drip when they don’t. These individuals might constantly clear their throat, spit, or blow their noses.
They are convinced that the mucus is infected and will cause them harm. Often they will overuse non prescription nasal drops and sprays to try and minimise mucus.
This type of condition needs psychotherapy or psychiatric treatment. (15)
There are no stages associated with this condition. However one of the main causes of post nasal drip is inflammation of the nasal passages (rhinitis).
Rhinitis can be allergic or non allergic. When non allergic there are nine classifications. These are based on the causes and include medications, foods, hormones, infections and nasal abnormalities.
This type of rhinitis could be attributable to certain occupations or structural changes in the nose associated with aging. It might also result from a decrease of the nasal mucus lining.
Sometimes the cause of rhinitis might be unknown. This is referred to as idiopathic or vasomotor rhinitis. (16, 17, 18)
Diagnosis of this condition will generally require an examination of the nose, ears and throat. It may require imaging scans to try and ascertain the cause.
Treatment can vary depending on the actual cause of post nasal drip and these include:
Bacterial Post Nasal Drip
Infections of the nasal passages or sinuses will generally be treated with antibiotics. If the cause is chronic sinusitis leading to bacterial infections, then surgery might be considered to drain the blocked sinuses.
Allergic Post Nasal Drip
When congestion leading to post nasal drip is caused by an allergy then the treatment will concentrate on the cause of the irritant.
Antihistamines, decongestants, steroidal nasal sprays or other types of steroids might relieve symptoms.
Injections or drops placed under the tongue (immunotherapies) are also options which can be considered.
Some antihistamines, especially older sedating ones, can dry or thicken the secretions which cause post nasal drip. There are however newer antihistamines on the market which don’t exacerbate symptoms. These are generally only available by prescription.
General Treatments for Post Nasal Drip
It might not always be possible for the cause of post nasal drip to be diagnosed. In these instances generic treatments might be considered.
These include increased fluid intake, avoiding the use of diuretics and reducing or eliminating caffeine intake. These things can help thin out mucosal secretions.
There are also medications such as humibid and robitussin which help thin mucus.
Flushing or irrigating the nasal passages might alleviate the symptoms associated with thickened mucus.
Using over the counter saline based nasal sprays can help moisten the nasal passages. (19)
Surgery might be considered if there are genetic defects contributing to post nasal drip. Nasal polyps, closed nasal passages or deformed nasal bones can be corrected.
Surgery is generally performed using local or general anesthetic, and it tends not to require a stay in hospital. (20)
What is post nasal drip? Post nasal drip is excess abnormal mucus draining from the back of the nose into the throat. It is generally a symptom of other conditions such as infections, allergies or nasal deformities.
What are the signs of post nasal drip? Signs associated with this condition are a cough, sore throat, nausea and bad breath.
How do you develop post nasal drip? This symptom is associated with conditions caused by viruses, bacteria, allergies and underlying medical conditions.
How are you diagnosed for post nasal drip? Examination of the nose, ears and throat, as well as imaging scans might identify the cause of post nasal drip.
What is the best treatment for post nasal drip? Treatment will generally depend on the cause, and includes medications and surgery.
What are the long term complications of post nasal drip? This symptom can be very irritating however identifying and treating the cause can provide relief.
Is post nasal drip considered a disability? Post nasal drip is not considered a disability.
Is there a cure for post nasal drip? Once the cause of post nasal drip has been identified, it can be treated successfully.
Is post nasal drip life threatening? Post nasal drip is not considered life threatening.
Post nasal drip is the result of excess abnormal mucus draining from the back of the nose into the throat. It is generally a symptom of other conditions such as infections, allergies or nasal deformities.
While diagnosis might not always be straightforward, once the cause is identified there are successful treatments available.