The "stuffy" nose.

Trouble breathing through the nose is one of man's most common disturbances. Sometimes this may be only a minor and temporary problem. Other times it may be a source of considerable discomfort or threat to health. Anything that interferes with the proper open nasal passage will cause an obstruction to the free flow of air through the nostrils and lead to nasal congestion. When this progresses, the person will have to breathe through their mouth. There are several categories of problems which cause nasal congestion.