Post nasal drip is dripping of mucus downwards from back of the nose or throat due to accumulation of mucous in the back of nose most commonly due to rhinitis (inflammation of nasal mucosa). Unless treated appropriately post nasal drip may lead to chronic cough and/or chronic sore throat. Post nasal drip is one of the causative factors for halitosis or bad breath.
What are the functions of nose?
Nose is responsible for warming, moisturizing (humidifying) and cleaning of air we inhale. Nose is also responsible for smell sense. Nasal mucosa produces mucus to perform its functions. Cilia (microscopic hairs) present in the nose help to brush away particles that are deposited from inhaled air and removed to the back of nose, which we swallow involuntarily. When there is excess mucus secretion it drips from back of nose known as post nasal drip.
What are the causes of post nasal drip?
Post nasal drip may be due to excess production of nasal secretions (mucus) by nasal mucosa or due to impaired clearance of the normal secretions.
Excess productions of nasal secretions may be due to:
- Allergies, viruses
- Exposure to cold temperature
- Anatomical abnormalities such as DNS (deviated nasal septum, where nasal septum is deviated toward right or left) or large or hypertrophied turbinates.
- Certain foods, such as spices
- Hormonal changes as seen during pregnancy
- Side effects of certain medications (e.g. anti hypertension medications)
- Vasomotor rhinitis, a non allergic condition
Decreased moisture in mucus secretion cause thickening of mucus (which may have impression of increased mucus) and may also lead to development of post nasal drip.Following conditions may cause decrease liquid in mucus:
- Low humidity in environment,
- Infection of nose and sinuses
- Anatomical abnormalities in nose
- Foreign bodies in nose
- Irritants such as tobacco smoke, air pollution
- Certain medications such as antihistamines
- Old age
Impaired clearance of nasal secretions may be due to
- Problem in swallowing may lead to impaired clearance of nasal secretions. Swallowing problem may be associated with old age, stress, gastro esophageal reflux disease, narrowing of passage due to tumor, disorders of nervous system or muscles.
Post nasal drip is mainly associated with rhinitis, sinusitis (inflammation of nasal and para-nasal sinuses), and diseases of esophagus such as GERD (gastro esophageal reflux disease) and any motility disorders of esophagus. Rhinitis is most commonly involved in post nasal drip and most common cause of rhinitis is allergy. Rhinitis is less commonly caused by non allergic conditions.What are the symptoms associated with post nasal drip?
- Rhinorrhea or runny nose
- Nasal congestion or blocked nose
- Constant swallowing and frequent spitting.
- Coughing, wheezing, and snoring.
- Itching in throat and constant clearing of throat.
- Husky, broken or cracking of voice
- Recurrent or chronic sore throat
- Burning sensation of throat or back of nose
- Halitosis or bad breath
If you have any of the above symptoms, make sure to consult your otolaryngologist (ENT or ear-nose-throat surgeon) for appropriate treatment of post nasal drip.