Allergies Or Illness: How To Tell The Difference

Allergies and colds can cause similar symptoms that make it confusing to distinguish which one the sufferer is experiencing. When sufferers misdiagnose their symptoms, it can lead to a mistreatment and therefore a worsening in sickness and symptoms. In order to accurately diagnose which problem you’re suffering from, it’s important to first understand the definition and differences between both conditions.


Allergies occur when the immune system overreacts to conditions in the environment or bodily reactions to certain chemicals. Substances that are usually considered harmless, such as pollen, animal hair and saliva, or dust, can cause the body to mistake them for germs that cause cold. The body then attacks these chemicals. Sufferers of allergies will experience histamine, a natural chemical the body expels during a cold.

Other substances that can cause allergies include medicine, food, mold, animal dander, and stings from various insects. Sufferers will experience symptoms such as sneezing, rashes, itching, runny nose and eyes, and inflamed lungs.

The Common Cold

The common cold is caused by a multitude of viruses, which causes your body to appear like it’s fighting infection as you become exposed. Viruses that cause the common cold are contagious, received by other people who are experiencing or just carrying the germ. The common cold usually occurs for a few weeks at the most. Symptoms of the common cold include sore throat, sneezing, congestion, runny nose and eyes, and coughing.

How to Spot the Difference

Although symptoms and other characteristics of both medical conditions seem the same, there’s small differentiating factors that will help you diagnose your symptoms as either an allergy or the common cold.

Onset of Illness

  • Common Cold: Symptoms of the common cold will occur a few days after the body is exposed to a virus.
  • Allergies: Symptoms of an allergy usually appear immediately after sufferers have been exposed to the substance.


  • Common Cold: The common cold occurs mostly in the winter; however, it’s possible to experience at any time of the year.
  • Allergies: Some allergies are seasonal due to substances like pollen. Other allergies can occur any time during the year.

Duration of Symptoms

  • Common Cold: Symptoms of the common cold will last anywhere from 3 to 14 days.
  • Allergies: Allergy Symptoms will occur as frequently as possible when sufferers are exposed to the substance.

General Symptoms

  • Common Cold: When having a common cold, a sore throat and coughing is frequent and can be severe. Other symptoms, such as aches and fatigue are common, but don’t always occur. A Fever, watery eyes, and running nose will rarely be experienced.
  • Allergies: The most noticeable symptoms for allergies is running and itchy eyes and nose. Other symptoms include coughing, fatigue, and sore throat, although not common. The main difference between allergies and the common cold is that sufferers of allergies will never experience a fever.
  • CC images from WikiMedia

An avid blogger from Austin, Peter Wendt loves the outdoors. Unfortunately, his sinuses don’t share this same appreciation for the hill country, and his children share some of the same allergies. Peter, of course, didn’t know this until he took his family in for seasonal asthma and allergy evaluations at Kangos Pediatrics.