What causes a bunged-up nose and a runny nose? A bunged-up nose is caused by inflamed nasal tissue and a runny nose is caused by too much nasal fluid.
What is the nose for? Most animals have one and they do pretty much the same function for all animals that have a nose. The nose warms the air that you breathe. The best temperature of air for our bodies is 37 ˚C. The air goes in through the nostrils and into the nasal cavities. There are bones that force the air through different passages and they make the air swirl, where it comes into contact with the lining of the nose and is warmed to the correct temperature. This is why it is generally better to breathe through the nose than the mouth. The nose humidifies the air as well. Our lungs prefer air that is at 100% humidity. This is also achieved by the lining of the nose. This lining is called the mucus membrane, and it allows water to mix with the air, moistening it. A third purpose of the nose is to filter out dust and particles before they can get to your lungs. This is done by the small hairs that line the inside of the nose. The mucus membrane seeps fluid onto these hairs, making them sticky enough to catch the particles. A fourth role of the nose is to direct air towards the olfactory epithelium, which detects the molecules in the air and translates them into scents. This is how we smell. The nose is also vitally important for keeping my glasses on my face.
So, what causes a bunged-up nose? There are many reasons why a person can have a stuffy nose, but the general way it forms is the same. The blood vessels inside the lining of the nose swell up, which makes the tissue around them swell up as well. Two of the most common reasons for this are a viral infection or an allergy. With a viral infection, the virus enters the body through the eyes, nose, and mouth. The viruses in the mouth can cause a sore throat, but the viruses that come in through the mouth start to multiply where they land, which is in the lining of the nose. The body does what it does best when you have a viral infection and tries to kill the viruses. The first reaction is to send in cytokines that make the tissue in the infected area to swell. These cytokines need to be sent in, so the blood flow to the infected area increases, making the swelling worse. The goal of making the area swell is to catch the viruses or give space to remove the dead viruses. If you have an allergic reaction, the same thing is happening as with a viral infection, except there is no invading body. The lining of the nose swells so much that it blocks the air passages, giving you a bunged-up nose.
A decongestant nasal spray can fix a bunged-up nose very quickly. They usually contain pseudoephedrine, which is a stimulant that makes veins contract and reduces inflammation. They shouldn’t be overused because the lining of the nose is very sensitive.
So, what causes a runny nose? A runny nose happens when the nose overproduces mucus. This can be because of an infection, or just because it is cold. Mucus for the mucus membrane in the nose is produced to keep the nose warm and moist. The nose usually produces just the right amount and any excess will run down the back of the throat. In the case of some viral infections, such as the common cold, the nose starts to produce more mucus in order to fill the nasal cavity. This is to stop the viruses from getting through the nose and spreading to the throat or lungs. There is more mucus than the nose can deal with, and it runs out of the nose. When you blow your nose, it empties the mucus in the nasal cavities for a while, but the mucus is soon replaced. We get a runny nose when it is cold because the nose is working harder to warm up the air that we are breathing. Air is obviously colder and drier when it is cold outside, so the nose produces more mucus to bring the air up to the correct temperature and moisten it. We also get a runny nose when we cry because the excess tears drain through the tear ducts and into the nose. They mix with the mucus that is already there and cause a runny nose. And this is what I learned today.
Sources
https://kidshealth.org/en/kids/nose.html
https://www.visiblebody.com/learn/respiratory/upper-respiratory-system
https://delmar.cz/en/noseandhealth/noseusage
https://en.wikipedia.org/wiki/Nasal_congestion
https://en.wikipedia.org/wiki/Decongestant
https://en.wikipedia.org/wiki/Pseudoephedrine
https://en.wikipedia.org/wiki/Rhinorrhea
https://vicks.com/en-us/symptom/nasal-congestion
https://my.clevelandclinic.org/health/symptoms/21660-inflammation
https://www.advil.com/symptoms-tips/cold-flu-sinus/congestion/truth-about-nasal-congestion/