Allergies vs Cold: What’s The Difference?

The difference between allergies and a cold can be hard to work out based on the early signs. Both cause similar symptoms, such as a runny or stuffy nose, sneezing, fatigue, and a sore throat.

However, they’re very different issues – and knowing which you have is important, so you can ensure you get the best possible treatment¹.

Fortunately, there are some key things that can help you tell if you’re coming down with a cold or experiencing allergies.

Discover what separates the two, how to identify one from the other and what to do if you experience symptoms with our useful guide.

You can even take our cold vs allergies quiz.

Is It A Cold Or Allergies I’m Experiencing?

The common cold and allergies share some overlap in their symptoms, but there are ways to tell them apart.

What Is A Cold?

A cold is an infection that can be caused by more than 200 different types of viruses². It usually affects your:

Nose
Throat
Sinuses
Trachea (windpipe)

Colds can be contagious up to two days before symptoms start, and can last for two weeks after exposure. There’s currently no cure for a common cold, but they’re generally mild and don’t normally result in serious health problems³.

What Are Allergies?

Allergies occur when your body’s immune system reacts to a foreign substance – such as pollen, mold, animal dander or certain foods⁴. For many people, coming into contact with these things will have no effect, but for those with allergies it can cause a reaction.

In this case, symptoms are a result of your body producing antibodies to fight off the allergen and remove it. As your immune system reacts, it can cause inflammation of your⁴:

Sinuses
Skin
Airways
Digestive system

Some allergies occur at a particular time of year, when the allergen is in the air. Symptoms can vary in terms of how long they last and their severity, depending on the allergen and your body⁵.

An important difference from colds is that they’re not contagious. Like the common cold, however, most allergies can’t be cured. That said, you can try to control and relieve your symptoms with an appropriate allergy treatment.

If you’re unsure what’s causing your illness, you can take our simple cold or allergies quiz to learn the differences between cold and common allergy symptoms.

Cold Or Allergies Quiz

Want to quickly find out whether you might have a cold or allergies? Discover what may be causing you to feel sick, so you can get relief - and get on living your life! Simply answer each of the questions, and follow the arrows down to get an answer.

No

A thin, clear discharge is most likely a sign of allergies.

Yes

The most common symptom of both allergies and a cold is a stuffy and/or runny nose.

No

Allergies don’t usually cause a fever.

Yes

One symptom of a cold can be a low-grade fever.

No

Allergies are not usually accompanied by an aching body.

Yes

An aching body typically means that you have a cold vs. allergies.

Fast

Allergy symptoms typically flare up as soon as you come into contact with an allergen.

Slow

Cold symptoms have a gradual onset and might take several days to develop.

Warm

Allergies are more common during the warmer months, when the air is filled with pollen.

Chilly

Colds are more likely to develop in winter.

See a physician for a professional diagnosis and treatment options. To help find powerful allergy relief, learn more about the ZYRTEC® family of products. Then download the ZYRTEC® ALLERGYCAST® app* to get a daily pollen forecast and track your allergy symptoms.

* Standard data rates for your plan apply.

Symptoms Of A Cold vs Allergies

Colds and allergies have plenty of symptoms in common, which can make working out the root cause of your illness difficult.

With both, you can experience⁶:

Runny nose

Sneezing

Stuffy nose

Fatigue, tiredness and weakness

To figure out the difference between allergies and a cold, you’ll therefore need to consider further signs.

Common symptoms of a cold that are rare or don’t occur as often with allergies can include⁷:

General aches and pains
Thick yellow or green mucus
Fever (mostly in children)

Common symptoms of allergies that you’re less likely to have with a cold⁸ can vary (depending on the allergen and severity of your reaction), but may include⁹:

Watery, red or swollen eyes
Itchy nose, eyes or roof of the mouth
Thin, watery and clear mucus
Facial swelling

When Do Colds And Allergies Occur?

The time of year you start to feel unwell can also be another way of telling the difference between allergies and a cold.

Generally, you’re more likely to get a cold in winter¹⁰, as cold viruses spread faster in cold weather and immune systems may be weaker at these times. However, it’s still possible to catch a cold any time of the year.

Seasonal allergies, meanwhile, normally strike in spring, when triggers such as pollen generally become airborne¹¹. It depends on what you’re allergic to though, as trees, weeds, grass and other plants can pollinate at different times of the year in different locations.

It’s important to remember you can also experience allergies in fall and winter – for example, ragweed allergies are most common in September and October. Mold, meanwhile, can develop in wet, fallen leaves and as we spend more time indoors, winter allergies can become more prominent – due to things like dust mites and pet dander.

What Should I Do If I Think I Have Allergies?

If you’ve experienced any allergy symptoms, you should see a doctor to get a professional diagnosis and discuss your treatment options. They can confirm whether you have an allergy, advise on what may be causing your reaction, and suggest treatment to relieve your symptoms.

Possible options can include¹²:

Over-the-counter medication for allergy relief, such as the ZYRTEC® family of products
Avoiding your allergy triggers altogether – your doctor may suggest steps to do this
Immunotherapy, either through injections or tablets, to try to build up an immunity for severe allergies

Download the ZYRTEC® ALLERGYCAST® app* to get a daily pollen forecast, and track your allergy symptoms.

*Standard data rates apply.

If Allergy Medicine Doesn’t Work, Is It A Cold?

If prescribed or recommended medicine isn’t working, there may be a few explanations.

Allergy medicine will not treat a cold (and vice versa). So, if you’ve started taking allergy medication without a proper diagnosis, you may just have a cold
If you’ve had a professional diagnosis, it could be that you need to try another medicine¹³. If this is the case, speak to your doctor and they may suggest immunotherapy or another treatment

Also, make sure you’re using allergy medications correctly – such as pointing nasal sprays the right way and following the directions on any packaging. You could have your local pharmacist help with drug administration if you are unsure how to use a product.

Cold vs Allergies – FAQs

Will A Hot Shower Help Allergies?

Taking a hot shower after being outside can help to clean off any allergens (such as pollen) that are stuck to your skin. Steam from a hot shower can also help clear your sinuses and airways, providing relief from a stuffy nose.

Does Vitamin C Help With Allergies?

Vitamin C is an antioxidant that supports your immune system. There’s some evidence that it can help reduce allergy symptoms such as inflammation and swelling¹⁴, but it’s not conclusive. Increasing your vitamin C intake shouldn’t worsen your allergies, but it may not provide lots of relief.

What Can I Drink For Allergies?

Staying hydrated when suffering from allergies is important, so drink plenty of water, which can also thin your mucus and provide relief. Hot tea, broth and soup also provide mild relief as the steam can help clear your airways when you breathe it in.

Cold vs Allergies: What’s The Difference?