We produce mucus every day. In fact, our noses can produce up to a litre a day! But why do we need mucus? We need it in order to moisten the areas of the nose, throat, stomach and intestinal tract and trap bacteria and viruses before they can cause infection1.

Ordinarily, we won’t notice the mucus1. However, when our nasal membranes become irritated due to viruses, allergens, infections such sinusitis, dust particles, or airborne chemicals, they respond by producing more mucus which unlike normal mucus, is thin, watery, and runny2.

This excess mucus can either come out of the nostrils as a runny nose or run down the back of the throat as a post nasal drip1. Post nasal drip can cause a sore throat, throat clearing and often a chronic cough3. A prolonged episode of post nasal drip often presents after a viral upper respiratory infection2.

So why does a post nasal drip cause a dry cough? The excess mucus tickles the nerves of the nasopharynx2 (the space above the soft palate at the back of the nose, which connects the nose to the mouth4), which triggers a cough reflex2.

Chronic coughing is so common that it is rated as one of the most common reasons for seeing a doctor2, and post nasal drip is actually one of the most common causes of a nagging cough that just won’t go away1. Coughing can interrupt sleep, cause fatigue and can impair concentration and work performance2. Typically, patients with a post nasal cough will cough more at night2

Home remedies which may assist a post-nasal cough include inhaling steam from a hot shower or kettle. Nasal irrigations by way of saline nose sprays may also help clean out irritating secretions2. At the early stages of a post nasal drip, over the counter medications that include a decongestant5 may be used, to decongest the nose and prevent the nagging irritating cough. Should the mucus pool in the lungs a wet cough syrup containing a bronchodilator, expectorant or mucolytic may be used 6, 7, 8.

Go to for more information or speak to your doctor or pharmacist if you have any questions regarding your symptoms or to determine the most suitable treatment for your type of cough.

DISCLAIMER: This editorial has been commissioned and brought to you by iNova Pharmaceuticals. Content in this editorial is for general information only and is not intended to provide medical or other professional advice. This editorial has content that includes independent comments and opinions from independent healthcare providers and are the opinions and experiences of that particular healthcare provider which are not necessarily that of iNova Pharmaceuticals.

Name and business address of applicant: iNova Pharmaceuticals (Pty) Limited. Co. Reg. No.1952/001640/07, 15E Riley Road, Bedfordview. Tel. No. 011 087 0000. For full prescribing information, refer to the individual package inserts as approved by the South African Health Products Regulatory Authority (SAHPRA). Further information is available on request from iNova Pharmaceuticals.


  1. Web MD – What is post nasal drip ( Website accessed on 21 September 2018.
  2. Harvard Health Publishing – That nagging cough ( Website accessed on 21 September 2018.
  3. com – Chronic Rhinitis and Post-Nasal Drip Symptoms, Causes, Treatment ( Website accessed on 21 September 2018.
  4. Healthline – Nasopharynx ( Website accessed on 21 September 2018.
  5. Harvard Health Publishing – Treatments for Post-Nasal drips ( Website accessed on 2 October 2018.
  6. Equinozzi R, Robuschi M, on behalf of the Italian Investigation Study Group on Pholcodine in Acute Cough. Comparative efficacy and tolerability of pholcodine and dextromethorphan in the management of patients with acute, non-productive cough. A randomized, double-blind, multicenter study. Treat Respir Med 2006;5(6):509-513
  7. Truter I. Cough. Evidence Based Pharmacy Practice. SA Pharm J 2007;74(4):20-27.
  8. Van Schoor J. An approach to recommending cough mixtures in pharmacy. S Afr Pharm J 2012;79(6):30-33.