Nasal congestion is due to the blockage of the nasal passages. This can be most often caused by a cold and it resolves by itself when cold is gone. If someone is having nasal congestion off and on all the time than one needs to look for the causes of chronic nasal congestion. Most common causes of chronic nasal congestion are Allergic Rhinitis or Hay fever and Chronic Sinusitis. Other causes include certain medications and during pregnancy. Some patients may have structural blockage due to deviated nasas septum, where the cartilage that divides the nose is bent to one side. If chronic congestion is not treated it can cause sleep apnea, which in turn will cause several other medical problems.
Congestion can also have an effect on hearing and speech development. Severe congestion can result in facial pressure and pain as well as dark circles under the eyes. In most patients congestion switches back and forth from one nostril to the other.
The nose normally produces mucus which traps substances like dust, pollen, pollution and germs like viruses and bacteria. Mucus would normally flow from the front to the back and is swallowed. When excessive,it may flow to the front. Normally the musus is clear and watery. But it may become discolored due to pollution or infection.
Proper evaluation would include history and physical examination. If allergies are a possibility, one would need allergy testing. Common allergens would include pollens, mold, dust, dust mite and pets. Infection in the sinuses or structural blockage can be ruled out by taking a sinus X-ray or a CT scan. Treatment would depend on the cause of nasal congestion. For allergies, a combination of antihistamines, decondestants and intranasal steroids would help. If there is an infection some patients may need prolonged course of antibiotics. Some patients may need surgery.