Cold and Flu: When To See a Doctor

Cold & Flu, and when to see a Doctor

Cold and Flu: When To See a Doctor

The oh-so-common cold, and its relative influenza, or ‘flu’, become part of everyone’s life sooner or later – and usually sooner.

Both colds and flu are caused by viruses. The most common cause of the common cold is the rhinovirus.2 Flu viruses vary with the seasons and geographical areas. Colds and flu are similar, with some overlapping symptoms, but there are some differences too. For example, colds frequently cause nasal congestion or a runny nose, which is less often associated with flu, while symptoms of the flu are often more severe.

Colds typically have a gradual onset, developing slowly and producing the following symptoms:,3

  • fever up to 102 degrees Fahrenheit or 39 Celsius)
  • a runny or stuffy nose and congested sinuses
  • sore throat
  • cough (either dry or productive)
  • sneezing
  • muscle aches
  • headaches
  • watery eyes

Flu is much more likely to have a sudden onset and more severe symptoms, including:3

  • a fever over 39 Celsius
  • chills and sweats
  • extreme fatigue
  • muscle aches, especially in the back, arms and legs
  • cough
  • headaches

In most cases you don’t need to see a doctor with colds and flu, however, in some cases colds and flu can lead to a secondary bacterial infection such as pneumonia (an infection of the lungs), sinus or ear infections or strep throat.  Some warning signs in adults that may need medical attention include, but are not limited to include:3

  • very swollen glands in the neck or jaw
  • severe or persistent vomiting
  • chest pain or pressure, shortness of breath
  • trouble breathing
  • confusion, fainting 
  • a high fever
  • an extremely sore throat, and/or symptoms that get worse instead of better over a week or 10 days.

Some warning signs in adults that may need medical attention include, but are not limited to include:3

  • a high fever, any fever lasting longer than 3 days
  • fast or difficult breathing
  • raspy or wheezing breath sounds
  • a ‘barking’ or ‘croupy’ cough
  • bluish skin tone
  • an extremely sore throat
  • ear pain or drainage
  • extreme lethargy or irritability
  • symptoms that improve and then worsen
  • if the illness lasts longer than 10 days.3


  1. Common Cold in Babies. The Mayo Foundation for Medical Education and Research.Available at . Accessed September 2010.
  2. Common Cold Centre. Cardiff University. General common cold information. Available at: Accessed September 2010.
  3. American Academy of Physicians. Family Doctor – Colds and Flu.