Bad breath, or halitosis, is a disorder that usually occurs in the mouth. The odor is often caused by volatile sulfur compounds in which the bacteria (there are over 170 species) living in your mouth produce when they metabolize the food leftovers in your mouth. When air is expelled from the mouth, as when you exhale, the odor is detected.
Bad breath out of the nose or of places other than the mouth is an extremely rare case of halitosis. That is because when bad breath out of the nose is expelled, the air comes from the lungs and bypasses the mouth altogether. So, therefore, the volatile sulfur compounds that are the most common cause of bad breath are not even touched. It is most unusual for air coming out of the nose to smell bad. Yet, bad breath out of the nose is a very real case of halitosis that could be a symptom of an underlying condition that is more serious than a case of lack of proper oral hygiene.
When you have bad breath out of your nose, the first places you should look to are the sinuses, throat, and lungs. Sometimes, the condition may also involve the lower airways or the stomach. Infections or disorders involving these areas may be the cause of bad breath out of the nose.
But before you panic over a possibly nonexistent condition, confirm the existence of bad breath out of nose passages first. Your sense of smell may be off due to a viral infection or other forms of sinus irritation, so there’s a likelihood that your bad breath out of your nose may just be an illusion. Ask a friend for help in confirming the condition.
Nasal Passage Blockage
After confirmation that you truly have an existential bad breath out of the nose, then check if there are any blockages or obstructions in your nasal passages. Sometimes, these blockages could prevent normal airflow and drainage, causing bad breath out of the nose.
The blockage may be caused by some foreign object inside the nasal passage as when children like to stick things up their noses. Swimmers are also prone to nasal passage blockage when they inhale water through their noses and accidentally cause objects to get stuck in the nasal passages. Particles of food may also end up stuck in the nasal passages while vomiting. All these things could happen, which could, in turn, lead to bad breath out of the nose.
Also, blockage of the nasal passages will force you to breathe through your mouth, which could lead to dry mouth, which could, in turn, lead to bad breath.
Infections in the nose or sinuses, lungs, or the throat could also lead to bad breath out of the nose. This should be easy to determine as infections are always accompanied by other symptoms, such as swelling, redness, heat, or pain in the sinuses. If any of these symptoms are present, and you also have bad breath out of the nose, then an infection may be brewing. Consult your doctor for treatment.