Key takeaways:
Colds and allergies can both cause runny nose, congestion, and cough.
Allergy symptoms will often include more sneezing and itchiness than colds. And allergies aren’t contagious.
Some over-the-counter (OTC) treatments can be used as allergy medicine or cold medicine.
When you’re feeling crummy with a runny nose, cough, and congestion, you want that feeling to go away as quickly as possible. But it helps to know what’s causing it. That way, you know what to expect and how to best treat it. If you experience allergies, you know how similar they can be to a cold. Here’s how to tell them apart.
How can you tell the difference between allergies and a cold?
The easiest way to tell if you have a cold or allergies is to look at your symptoms, how you got them, and how long they’re lasting. Here’s a closer look.
Symptoms
Many cold and allergy symptoms are the same. But they share some important differences.
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Allergies tend to be more itchy in general — especially in the nose, throat, and eyes. If you find yourself constantly rubbing your nose or experiencing itchy, watery eyes, then it’s more likely to be from allergies.
On the other hand, if you have body aches or fatigue, then you’re more likely to have a cold. These symptoms aren’t common with allergies. And if you have a fever, it’s not from allergies. A fever means your symptoms are more likely from a cold or another infection like the flu.
Causes
To help you figure out what’s causing your symptoms, it helps to know what usually triggers allergies and colds:
Allergies are caused by allergens. Common allergens include outdoor triggers like grass, pollen, and ragweed, or indoor allergens like dust, mold, and pet dander.
Colds are caused by viruses. There are at least 200 different viruses that can cause the common cold. Rhinoviruses are the most frequent causes of colds. But other viruses — like parainfluenza and human metapneumovirus — can also cause colds.
If you feel worse after being outdoors during the springtime, a pollen allergy may be causing your symptoms. But if you spent time with someone sick and then started coming down with the sniffles, chances are you’re fighting off a cold.
Duration (length) of symptoms
Cold symptoms usually last about 7 to 10 days. Sometimes, it can take as long as 3 weeks for symptoms to completely go away. Allergy symptoms can last even longer. Seasonal allergies — like grass pollen or ragweed — can last for an entire season. And allergies to indoor triggers — like dust or mold — can linger year-round if you don’t get treatment.
Season
Sometimes, the time of year can give you a clue as to what you’re dealing with. Allergy symptoms are more likely to flare up between spring and early fall. Colds are more likely during the winter and early spring. That said, some allergies can happen year-round, and colds can also show up during the summer.
Allergy vs. cold symptoms
Sometimes, it can be hard to know if your symptoms are caused by allergies or a cold. To make matters more confusing, the flu or COVID-19 can also cause similar symptoms. But there are some key differences between cold and allergies, including symptoms and causes.
What do allergies feel like?
Allergies tend to feel itchy and uncomfortable. There are many types of allergic reactions. When it mainly affects the nose, it’s called “allergic rhinitis.” This is what people commonly refer to as “allergies” or hay fever. Symptoms can include:
What does a cold feel like?
Cold symptoms can include the following:
Runny nose
Cough
Congestion
Headache
Sneezing
Sore throat
Body aches
With so much overlap in the symptoms, it’s easy to confuse colds and allergies. But we'll help you figure it out.
Take our quiz: Cold or seasonal allergies
Treating allergies vs. colds
You might wonder if allergy medications can help with cold symptoms, and vice versa. Some over-the-counter (OTC) medicines overlap and can be used for both. There are plenty of options to treat symptoms related to allergies, including antihistamines, decongestants, and nasal sprays.
In the table below, we review popular cold and allergy medications.
| Allergy and cold medicines | Allergy treatment only | Cold medicine only |
|---|---|---|
|
|
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OTC medicine for both colds and allergies
Some medications may help your symptoms whether they’re caused by a cold or allergies. Examples include:
Nasal decongestants: These work by decreasing swelling in your nose, making it easier to breathe. A common nasal decongestant is oxymetazoline (Afrin).
Oral decongestants: Oral decongestants — like pseudoephedrine (Sudafed) — can also decrease swelling in your nose. But they might also cause side effects like trouble sleeping or increased heart rate.
First-generation antihistamines: Older antihistamines can dry up mucus and also make you sleepy. So, these common allergy treatments are often included in nighttime versions of cold medicine. Examples include diphenhydramine (Benadryl) and chlorpheniramine (ChlorTabs).
Pain relievers: Pain relievers like acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) can help with pain and discomfort that’s caused by either allergies or colds.
Allergy medicines that probably won’t help your cold
Some allergy medicines aren’t going to be helpful for your cold. But they can help you feel better when your symptoms are caused by allergies. These include:
Nasal steroid sprays: Inhaled steroid sprays work very well for managing allergy symptoms. Examples include fluticasone propionate (Flonase), triamcinolone (Nasacort Allergy), and mometasone (Nasonex).
Second-generation antihistamines: These medications can lower your allergy symptoms without making you tired. Examples include loratadine (Claritin), fexofenadine (Allegra), and cetirizine (Zyrtec)
Cold medicines that probably won’t help your allergies
Some cold medications focus on reducing your cough. These are less likely to be helpful when you’re experiencing allergy symptoms. For example:
Cough suppressants: Cough suppressants like dextromethorphan (Delsym) are most helpful for dry coughs.
Cough expectorant: Expectorants like guaifenesin are most helpful for wet coughs. They work by loosening the mucus in your throat and chest so you can cough it up more easily.
With all these OTC options, you may be confused about what to take for your cold or allergy symptoms. You can always ask your local pharmacist or contact your primary care provider with questions.
Keep in mind that antibiotics don’t work for allergy or cold symptoms. This is because antibiotics are designed to treat infections caused by bacteria.
How can you prevent colds and allergies?
The strategies for preventing colds and allergies are very different.
To prevent allergies, focus on identifying your triggers and avoiding them as much as possible. For example, if you’re sensitive to dust, cover your pillows and mattresses with special dust-proof covers. If pollen triggers your allergies, keep your windows closed during pollen season and wear sunglasses outdoors to lower the amount of pollen that gets into your eyes.
To lower your chances of catching a cold, focus on good hygiene techniques like frequent handwashing, taking steps for cleaner air, and staying up-to-date with vaccines.
What can you do if you’re still not sure if you have a cold or allergies?
If you have bothersome symptoms and can’t seem to figure out what’s going on, you may want to see a healthcare professional. They can help you figure out the problem and suggest ways to make you feel better.
If you have severe allergies, they may recommend that you visit an allergist to manage your symptoms. An allergist is a doctor who specializes in allergic reactions, asthma, and other immune system problems.
Frequently asked questions
Some allergy medicines can be used to treat cold symptoms. For example, a decongestant can help relieve a stuffy nose or sinus pressure, regardless of what’s causing it.
Older antihistamine medicines — like diphenhydramine — are allergy medicines that can help dry up a runny nose from a cold. Diphenhydramine is sometimes used in cold medicines to help you sleep. But newer antihistamine allergy medicines — like loratadine or cetirizine — don’t help treat cold symptoms.
Both allergies and a sinus infection can show up with congestion, headache, and cough. But there are some key differences. If you have facial pain, tooth pain, or fever, a sinus infection is more likely. Also, the headache from a sinus infection tends to be worse than a headache from allergies.
No, allergies won’t turn into a cold. But if you have frequent allergies, you may be more likely to develop a sinus infection. That’s because allergies cause inflammation in the sinuses, which makes it harder for mucus to drain. This, in turn, makes it easier for bacteria to grow and cause a sinus infection.
You may have noticed that the color of your mucus changes, ranging from clear to yellow and green. But the color of your mucus alone isn’t a reliable way to tell the difference between a cold or allergies. You might have clear or colored mucus with both a cold and allergies. To figure out the cause, consider the other symptoms you’re experiencing. For example, clear mucus along with sneezing and itchiness may point to allergies instead of a cold.
Yes, untreated allergies can leave you feeling unwell for days to months. And as the name suggests, seasonal allergies can last for an entire season. Similarly, if you’re allergic to an indoor trigger like dust or mold, you may continue to have symptoms until you get treatment or remove the trigger.
Some allergy medicines can be used to treat cold symptoms. For example, a decongestant can help relieve a stuffy nose or sinus pressure, regardless of what’s causing it.
Older antihistamine medicines — like diphenhydramine — are allergy medicines that can help dry up a runny nose from a cold. Diphenhydramine is sometimes used in cold medicines to help you sleep. But newer antihistamine allergy medicines — like loratadine or cetirizine — don’t help treat cold symptoms.
Both allergies and a sinus infection can show up with congestion, headache, and cough. But there are some key differences. If you have facial pain, tooth pain, or fever, a sinus infection is more likely. Also, the headache from a sinus infection tends to be worse than a headache from allergies.
No, allergies won’t turn into a cold. But if you have frequent allergies, you may be more likely to develop a sinus infection. That’s because allergies cause inflammation in the sinuses, which makes it harder for mucus to drain. This, in turn, makes it easier for bacteria to grow and cause a sinus infection.
You may have noticed that the color of your mucus changes, ranging from clear to yellow and green. But the color of your mucus alone isn’t a reliable way to tell the difference between a cold or allergies. You might have clear or colored mucus with both a cold and allergies. To figure out the cause, consider the other symptoms you’re experiencing. For example, clear mucus along with sneezing and itchiness may point to allergies instead of a cold.
Yes, untreated allergies can leave you feeling unwell for days to months. And as the name suggests, seasonal allergies can last for an entire season. Similarly, if you’re allergic to an indoor trigger like dust or mold, you may continue to have symptoms until you get treatment or remove the trigger.
The bottom line
Cold and allergy symptoms can sometimes feel similar, but there are some differences that can help you tell them apart. Itchy nose and watery eyes are more common with allergy symptoms. And if you’re experiencing fever or fatigue, that means a cold is more likely. Be sure to ask a healthcare professional you trust if you’re not sure what’s going on. They can help point you in the right direction.
Why trust our experts?
References
American Academy of Allergy, Asthma, and Immunology (n.d.). About allergists / immunologists.
American College of Allergy, Asthma, & Immunology. (n.d.). Environmental allergy avoidance.
California Air Resources Board. (2020). Air cleaning devices for the home.
Hayden, F. G. (2003). Introduction: Emerging importance of the rhinovirus. Disease-a-Month.
Li, S., et al. (2021). The association between allergy and sinusitis: A cross-sectional study based on NHANES 2005–2006. Allergy, Asthma & Clinical Immunology.
