Better Me

What’s the Difference Between a Cold and Allergies?

On your way home from work, you notice you have a pounding headache and a stuffy nose. You also feel a bit run down. Something is clearly settling in, but is it a cold or just seasonal allergies?

“It’s a common question  because their symptoms, especially when they’re mild, can be very similar,” said Lurlyn Pero, MD, an internal medicine specialist at Banner Health in Arizona. “However, the treatments are quite different.”

Colds versus allergies

Colds are infections of the upper respiratory tract (this is the sinuses, nasal passages, throat and larynx). They are caused by several different viruses but can be spread by touching a person with a cold, or an object touched by someone with a cold, and breathing the virus in the air after someone coughs or sneezes.

Seasonal allergies, also known as hay fever or allergic rhinitis, occur when your immune system reacts to foreign substances – such as dust mites, exposure to pollen, insects, grasses, pet dander, mold and more. Allergies often run in families.

With both colds and allergies, it’s typical to have congestion or a runny nose and to sneeze often. You may also feel a bit run down or tired, but several other symptoms don’t overlap.

If you’re on the fence on whether to pop an allergy pill or watch Netflix and chill with your cold, here’s how to recognize the symptoms of a cold versus the symptoms of allergies so you’ll know what to do next.

Colds typically produce productive (phlegmy) coughs

Coughing is often a symptom of both allergies and colds, but a cold cough is typically wet and hacking. As symptoms go on with a cold, you can develop a thicker mucus, but allergies usually don’t produce a wet cough.

“Allergens typically cause irritation of the mucous membranes in the lining of the nose and nasal passages that results in a thin, watery mucus that drips down the back of the throat creating a tickling sensation in the throat,” Dr. Pero said. “It’s post-nasal drip that causes the cough.”

[Also read, “How to Safely Help Kids Manage a Nasty Cough.”]

Allergies rarely cause sore throats or body aches

Colds are viruses that affect the upper airway, so they can cause throat pain. The only throat pain you may feel with allergies may be due to irritation from post-nasal drip and a dry cough.

“If nasal congestion results from allergy symptoms, sometimes we unconsciously mouth breathe, especially when we’re sleeping,” Dr. Pero said. “This can result in a dry scratchy throat in the morning. This can often be remedied by drinking fluids in the morning or using a cool humidifier at the bedside overnight. 

You shouldn’t experience body aches and pains with allergies either. “If you have chills, it’s more likely you have a cold, the flu or another infection,” Dr. Pero said.

Allergies don’t cause fevers

Unlike the term “hay fever,” allergies typically don’t cause fevers. Colds are much more likely to elevate your body temperature or cause a fever than allergies. However, you could have an allergy flare-up at the same time you’re developing an infection.

“Allergies don’t cause infection but due to the inflammation, swelling and mucus that allergies can cause, this can cause mucus to get trapped in the sinuses and cause bacteria and viruses to grow,” Dr. Pero said. “This can result in sinus infections.”

Colds don’t tend to linger

A cold is generally more severe the first week and then will start to improve after 10 days. If you continue to get sick, you may be suffering from an allergy rather than a cold or viral infection.

With allergies, your symptoms may flare up at certain times throughout the year or when exposed to an allergen (such as a pet) and can last for several weeks until that particular allergen has ended or been removed.

“It’s important to note that allergies aren’t always confined to the spring and summer and colds to fall and winter,” Dr. Pero said. “Although we do see an increased frequency of cold viruses in the fall and winter months, colds and viruses can occur year-round.”

Allergies cause itchy, watery eyes

If you’re wanting to scratch your eyes out, it’s most likely due to allergies than a cold. You may also experience itchy ears, nose, throat and skin. “Contact dermatitis is an itchy rash caused by direct contact with a substance or an allergic reaction to it,” Dr. Pero said.

Is it really allergies or a cold, or do you have COVID-19?

We should all keep in mind that we are still living in a global pandemic, and COVID-19 symptoms often mimic those experienced with allergies, the common cold and the flu. 

“Before assuming that you’re experiencing a cold or allergies, particularly if you’re off to work or a social gathering, it’s always wise to seek advice from your health care provider,” Dr. Pero said. “It doesn’t hurt to also take an at-home COVID-19 antigen test, particularly if your symptoms are suggestive of a cold, and if your symptoms aren’t at a time when you typically experience allergies.”

How to treat colds versus allergies

If you have a cold, the best thing you can do is rest, drink plenty of fluids and treat your symptoms with over-the-counter medications until they subside. You should also stay away from others so they can keep from catching what you have. So, this is a perfect time to binge a show on Netflix.

If your cold isn’t getting better after a few days, don’t hesitate to reach out to your health care provider or find an urgent care to get your symptoms checked out by a professional. To find a Banner Health specialist near you, visit bannerhealth.com.

For allergies, drink plenty of fluids, take allergy medications to reduce symptoms and try to avoid the allergen in question, if possible.

“If your allergy symptoms linger, talk to your health care provider about allergy testing to identify what allergies you may have and what treatment options may work best for you,” Dr. Pero said.

Tips to prevent both

While you can’t 100% prevent either from occurring, there are some things you can do to reduce your risk. These include:

  • Practicing good handwashing habits
  • Avoiding others with a cold or other infection
  • Avoiding things that make your symptoms worse
  • Keeping your immune system strong by exercising regularly, eating healthy and getting plenty of sleep

“Some studies have shown a small benefit from vitamin C,” Dr. Pero said. “Other supplements such as vitamin E, Echinacea or zinc don’t have strong enough evidence to recommend their use for prevention of upper respiratory infections.”

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