What is the difference between a cold and an allergy?

Sherrie Pierce, DNP
Nursing Specialist

Telling the difference between cold and allergy symptoms can be difficult to distinguish even for health care providers. I explain it to my patients like this:  If it is allergies you will have sneezing, itching, nasal congestion and a clear watery nasal drainage (most of the time). If you have a cold you may have a fever, a more persistent sore throat, cough, general malaise and a thicker mucous but clear runny nose (most of the time). Nasal drainage can sometimes be cloudy or darker, especially in the morning, and this does not necessarily mean you need an antibiotic. Treat cold symptoms with fluids, rest and good nutrition and see your health care provider if symptoms last longer than 7 days or worsen.

Allergic rhinitis symptoms (red, itchy eyes; stuffed-up nose; sneezing) are often mistaken for those of a cold. So what are the main differences? With allergies, these symptoms can continue for weeks or sometimes for the whole year; with a cold, the symptoms persist for approximately 10 days, and then they disappear. Also, nasal discharge from an allergy sufferer is typically clear and thin, while people with a cold will often have a thick, yellowish discharge that results from infection.

Unfortunately, there's no reason that the two can't tango together! When your nasal membranes become irritated by constant sneezing and sniffling brought on by allergies, it's easy pickin's for viruses and germs to move in and cause an infection.

Here are some tips for telling the difference between a cold and allergic rhinitis:

  • Colds: fever common
  • Allergies: no fever
  • Colds: very contagious
  • Allergies: not contagious
  • Colds: frequent muscle or joint aches
  • Allergies: no muscle aches

There are several ways to tell if you have a cold or seasonal allergies. A cold is usually a self-limited viral illness that tends to run it's course in seven to 14 days. Seasonal allergies tend to run a longer course, may return every year or around certain exposures and are often characterized by runny, itchy eyes, sneezing, perhaps a cough, mild headache or fatigue. A cold may present with fever, nasal congestion, facial pressure, a productive cough, sore throat, headache and fatigue.


Telling the difference between colds and allergies can be difficult because they can have many of the same symptoms, such as runny or stuffy nose, sneezing or coughing. However, sore throat and fevers are more common with colds. If you are having itchy or watering eyes, this could be more likely with allergies but is not impossible with a cold. A pattern to your symptoms may also tell you more: If you wake up without symptoms, and then they start becoming bad after going outside, then it may more likely be due to being exposed to allergens, and thus, allergies again.

Both a cold and allergies can cause a runny nose, nasal congestion, coughing, sneezing and sore throat. While a cold typically lasts a week or two, allergies tend to last longer, such as 6 weeks for ragweed or grass pollen seasons. Allergies never cause aches or pains or fever.

Dr. Leigh Vinocur, MD
Emergency Medicine Specialist

Cold symptoms and allergies are somewhat similar. Colds almost always include cough and congestion with a yellowish mucus discharge as well as occasional muscle aches, fatigue and sometimes fever. Most colds usually begin with a sore throat. Allergies symptoms almost never include a fever or sore throat; the most common allergy symptoms are itchy, watery eyes and clear mucus congestion or postnasal drip.

Colds can last anywhere from a few days to 2 weeks, whereas allergy symptoms can last for months. Colds occur in winter months most often, but can occur at anytime. Allergies, especially seasonal ones, usually appear in spring due to flowers and tree pollen, and the fall for grasses. However, mold and dust allergies can occur anytime.

Dr. Peter N. Mattar, MD
Family Practitioner

Differentiating between cold and allergy symptoms can be challenging. Cold symptoms include runny nose, cough, fever at times, head congestion, sore throat, and/or headache. Allergy symptoms include clear runny nose, postnasal drip causing itchy throat, watery itchy eyes, and/or sneezing. Colds last few days to a week, but allergy symptoms can last for months at a time. Although colds and allergies can occur any times, colds usually occur in the winter months while allergies usually peak in the fall and spring.

A cold is a respiratory infection caused by a virus. An allergy is your body’s response to a substance (trigger) in the environment, such as pollen or dust. Both can cause a stuffy nose and other symptoms. However, colds go away in about 7 to 10 days. Allergy symptoms tend to last longer. Allergy symptoms tend to worsen during certain times of the year when environmental allergens are present.

Stacy Wiegman, PharmD
Pharmacy Specialist
The difference between a cold and an allergy starts with the causes of each condition. A cold is an infection caused by a virus. An allergy is the body’s reaction to an allergen, a substance (such as pollen) that your immune system views as an invader. A cold will typically last for a week to 10 days, while an allergy continues for as long as you’re exposed to the allergen. Colds are most common during the winter, but allergies can occur any time—usually in spring and fall. A cold evolves, starting with a runny or stuffy nose, mucus that may turn yellow or green, and a sore throat. An allergy occurs when you’re exposed to the allergen. Your nose runs with clear mucus, you sneeze and your eyes itch.
The difference between a cold and an allergy is that a cold is caused by a virus and allergies often occur in response to irritants like dust mites, pollen or ragweed.
Dr. Alan M. Young, MD
Family Practitioner

There are a number of differences between a cold and an allergy. Usually the common cold is going to cause a sore throat. That will be a major component of early symptoms. That progresses to a stuffy nose and cough which lasts for 7 to 14 days in most people.

Predominant allergy symptoms include sneezing, watery eyes and nasal itching. Sometimes the top of the mouth will feel itchy and discoloration will appear under the eyes. Allergies are often a long-term issue; they don't usually resolve after 7 to 14 days like a cold does. They tend to last as long as that particular allergen is present, often for several weeks or a month.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.