What causes you to bleed from the mouth and nose?

The medical term for nose bleeding is epistaxis.   Nose bleeding can be located from the front portion (anterior) of the nose or the rear (posterior part of the nose).

There are four different major reasons for nose bleeding and possible apparent mouth bleeding.

TRAUMA

There is a piece of cartilage between the right and left the side of your nose called the septum.  The septum can often be bent.  It can also have spurs of tissue growing on them.  A normal nose in a dry, non-humid environment can handle the air flow without drying the tissue covering the septum to the point it becomes brittle an easily can bleed.   Think of a nozzle of a water hose.  When you want the water to squirt out faster, then you narrow the hole at the end of the nozzle.  The same thing can happen to a nose with a bent septum and or spurs. The narrowness of the passageway causes air flow speed to increase.  This causes less time for the tissue to recover from the dry air and the tissue (its actually called mucosa) becomes more brittle/fragile and can flake off and start bleeding.   This will cause anterior nasal bleeding.  So under these circumstances, you would not have blood coming out the mouth as well.  This type of bleeding will usually stop spontaneously with a little pressure.  You should buy a humidifier if you sleep in a dry environment and have repeated nose bleeds.

There is also a danger associated with a person who uses topical nasal steroids.  Chronic steroid use can cause the tissue to thin.  This can thin the tissue covering the septum and make it more susceptible to bleeding.

The use of cocaine can cause bleeding even after only one-time use.  But prolonged use of cocaine can lead to the death of areas of the septum and cause perforations (holes between each nostril).  Once the septum is perforated it can be subject to bleeding at any time, but usually, there is some factor that is initiating the bleeding.  (Cocaine is a powerful constrictor of blood vessels. If the blood vessels to the septum are continuously closed off then the septum dies.)

All to the above would likely only cause bleeding to drip from the front of the nose and not cause any blood coming from the mouth.

(Did I forget to mention nose pickers and forceful nose blowers? But they won't have blood coming from both mouth and nose.)

BLEEDING PROBLEMS

Anyone who is taking blood thinners of any type can have bleeding occur from both the anterior and posterior parts of the nose.  If the bleeding is coming from the posterior it will normally go down the back of the throat.  But if someone is leaning forward it will go both ways.  In that case, it may appear that someone is bleeding from both the nose and the mouth if the bleeding is heavy.

There is also a hereditary disease called Osler-Weber-Rendu syndrome.  It is autosomal dominant meaning half the children of this gene will get this syndrome.  This syndrome appears in the patient's thirties or later and causes abnormal small dilated blood vessels in the nose lips, tongue, and also vascular malformations in the liver, lungs, and brain.  So this could cause bleeding to occur at any time from both the nose and the mouth.

CANCER OR INFLAMMATORY DISORDERS

This is the reason that if you have blood coming from both your nose and mouth you need to see a nose and throat (ENT) doctor asap.   Everything is possible if you have one of these disorders.

POST SURGICAL

If you have had any surgery or laser procedures are done to your nose or to the back of your throat, then you need to follow up with your surgeon immediately or go to the nearest ER post haste if you start bleeding
                                           
                                     

Michael Fiedler