Causes of Post Nasal Drip Chicago

Upper respiratory infection (common cold)

  • Drainage can be clear, yellow, or green
  • Associated with nasal congestion, runny nose, sneezing, and low grade fever
  • Symptoms typically resolve after 7-10 days
  • Strong odors / spicy foods

Allergies (hayfever, allergic rhinitis)

  • Drainage is clear and frequently associated with sneezing, runny/itchy nose, nasal congestion, and itchy/watery eyes
  • Symptoms can occur seasonally and/or year round
  • Allergy symptoms usually respond to anti-histamines, nasal steroid sprays (i.e. Flonase, Nasonex), and allergy eye drops
  • Symptoms of allergy-induced asthma such as coughing, wheezing, and shortness-of-breath may also be present

Strong odors / spicy foods

Hormonal changes

  • Birth control pill
  • Pregnancy

Bacterial sinus infection

  • Acute sinus infection
    • Symptoms typically last longer than 10 days but less than 6 weeks
    • Mild sinus infections have similar symptoms as the common cold
    • Yellowish/ green drainage
    • Fever may be present
    • Pressure over forehead and cheekbone
    • Frequently resolves without antibiotics
  • Chronic sinus infection
    • Symptoms lasting longer than 6 weeks
    • Nasal congestion (stuffiness) and decreased sense of smell are almost always present
    • Frequently associated with green/yellow nasal discharge and post nasal drainage


Asthma is a common cause of a chronic cough. It is usually, but not always associated with wheezing, chest-tightness, and shortness-of-breath. If you experience a deep cough in addition to post nasal drip, asthma may be contributing to your symptoms. Asthma frequently occurs with hayfever / allergy symptoms and acid reflux.

Acid Reflux

Acid reflux is a very common cause of PND and is referred to as Laryngo-Pharyngeal-Reflux (LPR) when it affects the throat. Acid reflux can move up into the throat, voice box, and sinuses and cause inflammation. It can lead to the same PND symptoms as many of the other causes.

  • Clues that Acid reflux is contributing to your PND:
    • Post Nasal Drip, coughing, throat clearing, and hoarseness are common symptoms of LPR
    • Symptoms are typically worse after eating
      • Spicy foods and carbonated beverages are strong triggers of LPR. (If you have significant PND symptoms after eating spicy foods or drinking carbonated beverages, you are likely suffering from LPR.)
    • PND symptoms are also significantly worse at night
      • The most severe form of LPR occurs when someone is sleeping and acid is swallowed into the lungs. The person can wake up with a feeling that they are severely choking. This tends to be a very scary experience that can last up to 10-15 seconds. This is referred to as Laryngo-spasm and occurs when the vocal cords close shut to prevent more acid reflux from draining into the lungs.
        • Frequently, there will be a very sour and acidic taste in the person’s mouth
        • Other symptoms of acid reflux (heartburn) are often present
    • Symptoms of LPR do not have to occur with the typical symptoms of GERD (Gastro-esophageal reflux disease- heart burn, indigestion)
    • The mucus drainage can be clear, yellow, or green
    • When severe enough, symptoms can be very similar to a chronic sinus infection (yellow or green nasal drainage and nasal congestion)
    • Acid reflux (LPR) frequently occurs at the same time as other causes of PND such as allergies.
    • Symptoms of LPR start gradually and the patient rarely remembers when the symptoms first began. If your PND symptoms started abruptly (such as after a cold), then LPR is an unlikely cause of your symptoms. This is a point frequently missed by Ear, Nose, Throat Doctors (ENT), allergists, and primary care doctors. This is a very crucial point.
    • LPR can cause significant disruption in a person’s sleep leading to severe daytime sleepiness.
      • If you have symptoms that suggest LPR and you are very tired during the day, treating the LPR may dramatically improve your energy level
    LSN is a relatively common cause of PND that is missed in over 90% of patients.

    Laryngeal Sensory Neuropathy (LSN)

    • LSN is a relatively common cause of Post Nasal Drip that is missed in over 90% of patients.
    • The main symptoms of LSN include throat clearing, coughing, fullness in the throat, and a sensation of post nasal drainage. However, there is rarely any mucus or phlegm that is actually coughed up.
    • Patients with LSN have often seen many other doctors with minimal improvement in symptoms despite aggressive treatment for allergies, sinus infections, or acid reflux. Patients are often told by their ENT doctor that the back of their throat looks "normal".
    • The cough is mainly throat clearing but can also be deep, severe, and hacking. Patients typically say that the cough begins as a "tickle in the throat".
    Approximately 85% of patients with LSN can be successfully treated

    LSN typically begins abruptly following an Upper Respiratory Infection (common cold). In fact, one of the important clues that LSN may be the cause is that patients can often remember the approximate time when their symptoms began. And many will state that it began following the cold. There are very few causes of throat clearing / coughing that begin so abruptly. Most of the other causes of throat clearing / coughing that begin abruptly such a sinus infection or cold typically resolve readily on their own of following a course of antibiotics. The symptoms of LSN may not resolve for many months or even years without treatment.

    What causes Laryngeal Sensory Neuropathy (LSN)?

    To understand what causes LSN, I have to explain the “cough reflex.” The cough reflex is a protective mechanism we all have that helps prevent us from choking and suffocating from a swallowed object. When food (or another object) gets stuck in our throat, our brain is immediately alerted by the nerve tissue in the throat or airway that leads into the lungs. We immediately start to gag as the muscles in our throat and chest begin to contract so that we may be able to expel the object. Sometimes, however, the brain is tricked into thinking that something is stuck in the throat and/or airway. This is exactly what happens with LSN. Symptoms usually start with the common cold. The cold causing virus damages the nerve tissue in the throat and airway. A message is sent to the brain saying something is caught in the throat. This message is a false alarm however. There is actually nothing wrong with the throat, but your brain thinks that there is. So a person suffering from LSN will clear their throat or cough because the brain thinks there is a foreign object that has been swallowed. In other words, to the patient- it feels like there is actual drainage or something stuck in the throat. But this is just a “feeling” that is caused by a false signal from the brain.

    • Most doctors do not understand that this is a common cause of throat clearing and coughing. And symptoms can last for over 20 years without being recognized and treated.
    • Triggers for the cough include laughing, talking and strong odors. Symptoms usually do not occur while sleeping.
    • LSN can occur by itself or with other causes of PND such as allergies, asthma, and acid reflux.

    Post Nasal Drip treatment