Mucus is produced by some specific glands in the nose, threats, airways, stomach and even intestines. The nose, however, produces about a quarter of the total mucus in the body per day. Mucus is a wet substance that helps in moistening these areas and also to trap foreign substances and bacteria.
When the body produces more mucus than is necessary the excess comes out of the nostrils called ‘running nose. When the mucus goes down from the nose to the throat is called post nasal drip.
Postnasal drip is caused by a wide range of things such as common cold, flu, allergies, sinusitis, foreign objects in the nose (mostly in children), pregnancy, some certain medications especially antihypertensive drugs and birth control drugs, deviated nasal septum, dry air, inhalation of some chemicals such as house cleaning agents, perfumes and some other irritants. Other causes may include gastroesophageal reflux disease.
Postnasal drip is characterized by the constant feeling of wanting to clear the throat, cough (which often gets worse act night), sore throats and ear pain.
The treatment is based on the underlying cause. Antibiotics can be used to clear away a bacterial infection but viral infections remain unaffected by antibiotics. Antihistamines and nasal decongestants are used to clear postnasal drip caused by a sinus infection and other viral infections. Nasal sprays can be effective for post nasal drips caused by allergies. If the drainage has an offensive odor or there is a fever, it is better to make an appointment with the doctor. Also if there is blood in the discharge or if the symptoms are severe, an ENT specialist (otolaryngologist) is to be visited from proper examination. An imaging test such as a CT scan or MRI scan may be required.