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Doctor, why is my nose full of mucus?

Good morning and TGIF!

Welcome back to Dr Euan's ENT Friday blog!

The topic for today's blogpost is about runny nose & mucous from your nose.

Dr Euan has also written a previous blogpost on snot that you can read here.

Q: What is mucus/snot?

Mucus is produced by the lining of your nose and sinuses, and serves to lubricate the delicate mucosa. Without mucus, the little cilia cannot function to remove dirt and microbes outwards for expulsion and eventually swallowed into the digestive tract or sneezed out. Other common terms are "snot" or"boogers" in more colloquial terms.

Endoscopic image of nasal passages blocked up by mucus

Q: Why do we have mucus in our noses?

Why you shouldn’t sniff at snot

Nasal mucus actually has a protective function for your airway and protects against viruses, bacteria,

and irritants like dust and debris from entering the nasal passages and lungs.

If you happen to develop extra mucus, such as when you have a cold or allergies, your body makes more to trap the germs or irritants and get them out of your body. This can also lead to what's known as 'post-nasal drip". While it may be an annoyance at the time, excess mucus can be a positive sign that your immune system is in action.

Q: What does the colour of the mucus mean?

Whether you are prone to bloody noses, allergies, or have a little booger factory at home (e.g., your child), you’re bound to notice changes in the colour and consistency of nasal mucus as well. It can sometimes be an array of colours, from red to green and black to yellow!

These changes can tell you a lot about an illness or infection your body is fighting and any situations or activities that may be affecting you. Although your GP will not use your nasal mucus as a primary diagnosis, it is important to be aware of any changes as it could indicate something is up with your health.

Your snot colour could indicate you’re fighting off allergens, you have a cold or a sinus infection. Maybe you have dry nasal passages, or are dehydrated.

As with any body part, when it comes to your nasal passages, you should be aware of what is ‘normal’ for you and distinguish any departure from that norm.

The next time you sneak a peek at your used tissue, here is what to know about the texture and colour of your snot:

Clear mucus

Clear snot is generally considered normal. Clear mucus is mostly saltwater, with locally produced protective antibodies.

Most of the time you do not even notice mucus doing its job unless you notice more mucus production and phlegm. Increased amounts of clear mucus are often part of an allergic reaction to substances such as Dust Mites or Pollen. In such cases, taking antihistamines might be helpful to clear nasal congestion.

Endoscopic image of post-nasal space with excess clear mucus

White thick mucus

White snot is an indicator of slow-moving mucus or a sign that you may be dehydrated.

If the salt water is evaporated or dried out, what is left is white mucus.

This is usually not something to be too concerned about. You should drink more water to re-hydrate your body.

Red or pink mucus

Red or pink snot is most likely related to blood from a dried out or irritated nose.

This can occur from nose bleeds from continual blowing of your nose, nasal trauma or damage, or picking your nose too hard due to allergies.

In some cases, more sinister abnormal growths can cause blood in the nasal mucus. This can include growths such as nasal polyps or papillomas, or cancer. In Chinese patients, Nasopharyngeal cancer is still in the TOP 10 cancers for adult males.

Yellow or green mucus
Yellow or green mucus may be a sign of sinus infection

If you see green or yellow mucus or phlegm, it may be a sign your body is fighting a viral infection or allergies, but also may eventually resolve on its own.

The colour comes from white blood cells that are battling viruses, bacteria and irritants. When they’ve done their job, they get flushed out of your body along with the virus or bacteria.

Saline irrigation of the nose, or using decongestant nasal sprays may help to reduce or eliminate the coloured mucus and hasten your return to a “normal state.” However, if this mucus persists for more than 7 to 10 days and includes congestion, sinus pressure, headache, fever and other symptoms, it could be a bacterial infection or sinusitis. Do consult your GP or ENT specialist then as you may need a course of antibiotics to help clear the infection.

Brown mucus

Dried or crusting blood may give your nasal mucus a brown tinge of colour. Outside irritants such as dust and dirt will also give the mucus a brownish colour.

Black mucus

Similar to brown snot, black nasal mucus can be the result of dried blood, or from inhaling something dark like cigarette smoke, smog or dust. However, in some cases, it can also be a symptom of a fungal infection, which tends to affect people with a compromised immune system. Do see your GP or ENT specialist if your symptoms continue.

Q: When you should I seek treatment for excess mucus?

Embarrassing or not, it is so important to be in touch with your body—and your snot. If you notice changes and have concerns, you should take notice.

Also, if you have found that hydrating, saltwater irrigation of the nose and/or the use of allergy medicine don’t return your nasal mucus back to normal, a medical evaluation is recommended.

Well, I hope you have found this post on SNOT useful! if you are keen to learn more, here are some useful references to look up!

Have a great weekend :-)

Dr Euan

If you would like to consult an ENT specialist about nasal mucus, or any other Ear, Nose, or Throat related conditions, please feel free to Contact Us at Euan's ENT Surgery & Clinic to make an appointment.

Contact No. : 6694 4282


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