Post nasal drip is the virtually constant sensation of mucus dripping down or sticking in the back of your throat. It’s not a condition in and of itself, but rather a symptom of a variety of different sinus and respiratory conditions (like rhinitis). Here is a look at some of the underlying causes of post nasal drip.
Why Mucus?
Your body is constantly making mucus. There are glands all over the respiratory system, from the nose to the lungs, that make mucus by the quart on a daily basis. This mucus helps capture dust, keeps the airways moist, keeps the membranes in your nose clean and hydrated, and helps fight off infections all by moving foreign bodies—like bacteria and dirt—out of the sinuses and nose.
All of this occurs via the autonomic nervous system’s parasympathetic system; this is the same brain function that keeps your heart beating and keeps the intestines and other glands running efficiently. Producing mucus is an involuntary, natural occurrence. When the mucus glands are running normally, most people don’t even notice the mucus in their nose or throat, even when it’s being swallowed for disposal.
What is Post Nasal Drip?
Post nasal drip, however, is characterized by its obviousness. Namely, the mucus becomes overly thick or thin, physically noticeable, and drips down the back of the throat. It may even accumulate and feel like a lump in the throat. Mucus may become clearly present because the it changes consistency or because of an issue with the throat muscles that control swallowing.
Mucus Abnormalities
Mucus may become very thin for a variety of reasons. In many cases, sinus or respiratory disorders are the culprit. Allergic and nonallergic rhinitis often cause a runny nose (rhinorrhea); post nasal drip is essentially a backwards runny nose. You already know the mucus in your nose is in charge of getting rid of stuff that isn’t supposed to be there.
Thin Post Nasal Drip: According to Popular Science, during an illness, there are pathogens in the mucus that kick the mucus glands into high gear to clear them out. The lining of the nasal passages becomes inflamed and filled with extra fluid that thins out the mucus. Hormonal changes may wreak havoc on your mucus glands; pregnant women often experience excessive amounts of mucus. Birth control and blood pressure medications may thin mucus, as well. A deviated septum (when the thin layer of tissue that separates the nostrils is off center) is a structural issue that can contribute to post nasal drip. Other things that may thin out mucus include spicy foods, bright lights, and cold air.
Thick Post Nasal Drip: Respiratory illnesses can also make mucus thicker. Congestion is often a nasty side effect of colds that results in a thick green or yellow phlegm, sometimes treatable with antibiotics. Dairy products also tend to increase congestion, particularly if you have an allergy to them. In the winter months, mucus may grow thicker because of drier air, not only outside but because of indoor heaters that pull moisture from the air. This dries out and inflames the sinuses, causing thicker secretions.
Post Nasal Drip in Children: Post nasal drip in small children can be a result of a foreign object lodged in the nasal cavity (keep an eye on those crayons!). In either case, thick or thin, the mucus isn’t a normal consistency and becomes more obvious to the body: the thin as it drips more easily down the throat, the thick when it fails to slide easily down the throat.
Throat Muscles and Swallowing Disorders
According to the American Academy of Otolaryngology - Head and Neck Surgery, when a swallowing disorder is present, it interferes with normal swallowing. This means that what you swallow slowly creates a build up in your throat until it either feels like post nasal drip or worsens your existing post-nasal drip. Additionally, the extra mucus you’re trying to swallow can end up in the larynx, trachea, or bronchi causing hoarseness, coughing, and constant clearing of the throat. Gastroesophageal reflux disease (GERD) is also a common culprit of post nasal drip, as it contributes to swallowing issues.
