The deviated septum is happening when the thin wall (also known as a nasal septum) between the nasal passages is displaced to one side. There are many people in who the nasal septum is displaced or deviated which is making one nasal passage smaller. When the deviated septum is severe, then it can block one side of your nose and reduce the airflow which is causing difficulty breathing .
The additional exposure of the deviated septum to the drying effect of the airflow through the nose can contribute to bleeding or cruising in some individuals. The nasal obstruction can happen from a deviated nasal septum, from swelling of the tissues lining the nose or from both. The treatment for the nasal obstruction can include nasal dilators which can help to open the nasal passages or medications to reduce the swelling. Surgery is needed to correct the deviated septum.
Deviated Septum Symptoms:
In most cases, the deviated septum results in no symptoms, and you may not even know that you have deviated septum. But there are some septal deformities which can cause some of the following signs and symptoms:
Preference for sleeping on a particular side:
There are some people who prefer to sleep on a particular side in order to optimize the breathing through the nose at night. This can be caused by the deviated septum which narrows one nasal passage. 
Awareness of the nasal cycle:
It is known that it is normal for the nose to alternate being obstructed on one side and then changing being obstructed to the other side. This is known as the nasal cycle. The nasal cycle is a normal phenomenon. You should be aware that the nasal cycle is unusual and it can be an indication that there is an abnormal amount of nasal obstruction. 
Noisy breathing during sleep:
This can happen in infants and young children who have a deviated septum or who have swelling of the intranasal tissues. 
There are some debates about the possible nasal causes of facial pain, but the severely deviated septum which impacts the inside nasal wall when it is one the same side as one-sided facial pain is considered as a possible cause in some cases.
The surface of the nasal septum can become dry which is increasing the risk of nosebleeds. 
Obstruction of one or both nostrils:
The obstruction can make it difficult to breathe through the nose or nostrils. This can be more noticeable when you have a cold (upper respiratory tract infection) or allergies which can cause your nasal passages to swell and narrow. 
Deviated Septum Causes:
The deviated septum happens when the nasal septum (this is the thin wall that separates your right and left nasal passages) is displaced to one side. The deviated septum can be caused by:
Injury to the nose:
The deviated septum can be a result of an injury which causes the nasal septum to be moved out of position. During childbirth, there can be an injury to the infant. There are many different types of accidents in children and adults which can lead to a nose injury and deviated septum, such as tripping on a step and colliding with another person on the sidewalk. The trauma which is caused to the nose, most commonly happens during contact sports, automobile accidents, active play, or roughhousing. 
A condition present at birth:
There are some cases when the deviated septum happens during fetal development and it is apparent at birth. 
Also, the normal aging process can affect nasal structures which will worsen the deviated septum over time. Also, there can be changes in the amounts of nasal tissue (this can be caused by rhinitis or rhinosinusitis) which can accentuate the narrowing of a nasal passage from the deviated septum and this result in nasal obstruction.
Deviated Septum Risk Factors:
There are some cases when the deviated septum is present at birth which is caused during fetal development or due to injury during childbirth. After the birth, a deviated septum is most commonly caused by an injury which moves the nasal septum out of place and some risk factors are
- You are not wearing your seat belt while riding in a motorized vehicle
- Playing contact sports 
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