Cough Caused by a Virus

Virus infections commonly affect the throat (larynx), or the main airway (trachea), or the airways going into the lungs (bronchi). These infections are sometimes called laryngitis, tracheitis, or bronchitis. Cough is often the main symptom.

The cough typically develops over a day or so, and may become quite irritating. Other symptoms may develop and include: fever, headache, aches and pains. Cold symptoms may occur if the infection also affects the nose. Symptoms typically peak after 2-3 days, and then gradually clear. However, the cough may persist for up to 4 weeks after the infection has gone. This is because the inflammation in the airways caused by the infection can take a while to clear.

There is no 'quick fix' for a cough due to a virus infection. You need to be patient until the cough goes. Most viral infections go without treatment as your immune system clears the virus.

• Take paracetamol, ibuprofen, or aspirin to reduce fever (high temperature), and to ease any aches, pains and headaches. (Children under 16 should not take aspirin.)
• Have lots to drink if you have a fever, to prevent mild dehydration.
• A cough medicine that you can buy at pharmacies may help, but there is little evidence that they work. They often contain several ingredients in addition to those aimed at the cough. For example, some cause drowsiness, which may help with sleep. Some contain decongestants, which may help relieve a bunged-up nose. Some contain paracetamol, so be careful that you do not take these in addition to paracetamol tablets. Ask a pharmacist for advice.
• Antibiotics are not usually advised. Antibiotics do not kill viruses - they only kill bacteria. Antibiotics do not usually ease a cough caused by a virus. They may even make symptoms worse as they sometimes cause side-effects such as diarrhoea, feeling sick, and rashes.

Most viral coughs clear without complications. However, sometimes a 'secondary' infection with bacteria develops in addition to the viral infection. This may become serious and cause pneumonia. Also, other causes of cough (such as asthma) are sometimes confused with a viral infection. So, see a doctor if any of the following occur.

• If symptoms such as fever, chest pains, or headaches become worse or severe.
• If you develop breathing difficulties such as wheezing or shortness of breath.
• If you cough up blood.
• If you become drowsy or confused.
• If you develop any symptoms which you are unhappy about, or do not understand.
• If you have a cough that persists longer than 3-4 weeks.

© EMIS and PIP 2006   Updated: June 2006