Allergy vs. cold: how can you tell the difference?
LAST UPDATED: May 28, 2021
3 MIN READ
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You have a runny nose, coughing, sneezing, and congestion. Is it a cold, or could it be allergies? Allergies and a cold can have similar symptoms and share a common denominator: They can leave you feeling pretty miserable. But it's important to know the difference between a cold and allergies so you can treat the symptoms most effectively and find relief as soon as possible.
What is the “common cold”?
Millions of people get the “common cold” every year, if not several times a year. While we think of the common cold as a single illness, it can be caused by several viruses, including strains of coronavirus, adenovirus, respiratory syncytial virus, and enterovirus. However, rhinovirus is the most common culprit when it comes to catching a cold.
You are probably familiar with the most common cold symptoms like cough, sneezing, a runny or stuffy nose, headaches, and fatigue. There's a reason the cold is called “common”—the average adult gets 2–3 colds annually, and kids may get even more. In fact, having someone in your family at school or enrolled in daycare is a risk factor for catching a cold (Thomas, 2020).
Most people get a cold in the winter months, but you can certainly have one at any time of the year. Fortunately, the majority who catch a cold get better within a week or two. However, if you have a weak immune system or certain lung conditions, a cold can become a more serious problem like pneumonia or bronchitis (Thomas, 2020).
What are allergies?
Unlike the cold or flu, allergies are not caused by a virus. Rather, they are due to your immune system overreacting to typically harmless substances in the world around you—things like pollen, animal dander, dust, mold, and various foods (such as peanuts or shellfish).
Allergic rhinitis, or hay fever, is a common reaction to inhaled allergens, like pollen. Allergy symptoms can include sneezing, cough, skin rash, a runny or stuffy nose, itchy eyes, or watery eyes. If you have allergies, you are not alone—up to 30% of children and adults in the U.S. have allergic rhinitis (Akhouri, 2021).
Some people suffer from allergies only during certain seasons (like spring and/or fall), called seasonal allergies. Others may experience them year-round (perennial allergies) due to things like dust mites and flooring/upholstery.
Symptoms of allergy vs. cold
There are some similarities and differences to be aware of when comparing symptoms of allergies vs. a cold.
Several common symptoms of allergies and a cold overlap, sometimes making it difficult to tell the two apart. These include (Akhouri, 2021):
Runny or stuffy nose
Nasal, ear, or sinus congestion
Several telltale signs can help you determine whether you have allergies or are fighting a cold. This table summarizes these differences (Thomas, 2020; Akhouri, 2021).
When trying to figure out if you have allergies or just a cold, consider the time of year and your own allergy history. Do you have the same symptoms around the same time every year? Airborne pollen peaks in the spring, while ragweed makes many people miserable, starting around mid-August. But don’t forget that allergies can happen year-round (even in winter), especially if you are allergic to indoor allergens like dust mites and pet dander.
You can also think about the duration of symptoms: Cold symptoms usually take a week or two to improve, while allergy symptoms can stick around for weeks.
The most important criteria for telling whether you have a cold vs. allergies are those telltale symptoms. Allergies rarely cause a sore throat, headache, fever, and body aches, while the common cold rarely comes along with a rash or itchiness.
Diagnosing allergies vs. common cold
It’s not always as easy as it sounds when it comes to knowing whether you have allergies or a cold. When in doubt, talk to your healthcare provider, especially if your symptoms last longer than two weeks.
If your primary healthcare provider is unsure about your symptoms, you may need to see a specialist or an allergist. Sometimes, it is difficult to identify what you are actually allergic to—this is where allergy skin testing can help. Allergy skin testing can help determine which specific agents are triggering your allergies so you avoid them.
Most healthcare providers can diagnose a cold by asking you about your symptoms. However, if they suspect something more serious, your provider may order additional testing like an x-ray to look at your lungs or a strep test to check for strep throat.
Treating allergy vs. common cold
The best treatment for allergies is to avoid whatever you are allergic to—however, that is not always possible. You have several options for treating allergy symptoms, including over-the-counter antihistamines, nasal steroids, decongestants, and eye drops. If your symptoms persist or are severe, see a healthcare provider. They can prescribe prescription allergy medication, nasal steroids (which reduce inflammation), or allergy shots if necessary (Akhouri, 2021).
Decongestants, cough syrup, and nasal sprays can help with nasal congestion and coughing from a cold. Over-the-counter pain relievers such as ibuprofen or acetaminophen can lower fever and reduce body aches. Using an ultrasonic humidifier in your bedroom can moisten the air, which can help soothe a sore throat, nasal dryness, and coughing. But there is no cure for a cold in the end—only time and plenty of rest.
If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.
Akhouri S, House SA. (2021) Allergic rhinitis. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK538186/ .
Thomas M, Bomar PA. (2020). Upper respiratory tract infection. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK532961/ .