What Is the Difference Between a Common Cold and Allergies?

The line between a common cold and allergies may seem blurred by the similar symptoms they can cause, yet their origins and underlying mechanisms have key distinctions. Additionally, there are some specific symptoms that allow you to tell a common cold apart from an allergy. We’ll fill you in on those unique symptoms in just a moment.

First, we want to briefly explain the common cold and allergies in a biological context to you and showcase how they are caused, as this is important for your overall comprehension.

The Common Cold – (Viral) Groundhog Day

Did you know that the common cold is almost as old as humanity? Numerous historical records dating back hundreds of years describe people suffering from common cold symptoms. [1]

Most of us experience a common cold at least once or twice a year. But what exactly is the common cold, and how is it caused?

The common cold, a pervasive ailment affecting millions worldwide, is primarily caused by viruses belonging to the rhinovirus family, with over 100 known strains. However, other cold viruses, such as coronaviruses and adenoviruses, can also be the culprits. The common cold is mainly spread through airborne droplets that are coughed or sneezed into the air by a sick person and inhaled by another person, who then gets infected. [2]

Biological interactions play a pivotal role in the onset of a cold, as the virus gains entry through your nose or mouth, targeting the epithelial cells lining your upper respiratory system.

Once infiltrated, the virus rapidly replicates, triggering your immune system to respond. The characteristic cold symptoms, including sneezing, nasal congestion, fever, and coughing, stem from the immune response and the body's attempts to combat the viral invaders. [2]

Allergies – Airborne Culprits Confusing Our Immune System

Allergies, a complex immune system response, arise when your body's defense mechanism overreacts to typically harmless substances, known as allergens. These allergens include pollen, pet dander, certain foods, mold, chemicals, dust mites, or insect venom. [3]

Biologically, allergies involve the immune system mistaking those allergens for potential threats, which leads to the release of chemicals, such as histamines, to counteract them. This immune response causes the hallmark allergy symptoms, including an itching and runny nose, sneezing, and nasal congestion. Many people suffer from the so-called “hay fever,” which refers to seasonal allergies caused by airborne allergens like tree and grass pollen. [4]

While the term "allergy" is relatively recent, dating back to the early 20th century, historical evidence suggests that allergic reactions have likely been present throughout our human history. Ancient texts describe symptoms resembling allergic reactions, indicating that people may have experienced allergies long before the formal recognition and understanding of the allergic response.

Nowadays, nearly 1 in 3 adults and more than 1 in 4 children in the US have a seasonal allergy, eczema, or food allergy, according to data from the CDC’s National Center for Health Statistics in the year 2021. [5]

Cold Symptoms vs. Allergy Symptoms – Overlaps & Differences

Usually, the easiest way to distinguish between allergies or the common cold is to ascertain whether you have a fever and body aches. Allergies do not result in fever and body aches. [6]

Another good indicator is your nose and eyes – if they are itchy, chances are high that you are suffering from an allergy rather than having a cold. [6]

For your convenience, CARE compares the most common symptoms of allergies and the common cold below [6]:

Allergies vs. Common Cold – A Comparison of Symptoms

Onset of Symptoms
Common Cold: Gradual
Allergies: Sudden after-allergen exposure

Fever
Common Cold: Common
Allergies: Rare

Body Aches
Common Cold: Common
Allergies: Rare

Fatigue
Common Cold: Common
Allergies: Uncommon

Sneezing
Common Cold: Common
Allergies: Common

Nasal Discharge
Common Cold: Common, thick mucus
Allergies: Common, thin, clear discharge

Itchy Eyes/Nose
Common Cold: Uncommon
Allergies: Common

Watery Eyes
Common Cold: Common
Allergies: Common

Cough
Common Cold: Common, may be productive
Allergies: Common, often dry

Duration
Common Cold: 7–14 days
Allergies: Varied, depends on exposure

Seasonal Patterns
Common Cold: Winter
Allergies: Spring, Summer, Fall

Understanding these distinctions can guide you in determining whether your symptoms align more closely with a common cold or seasonal allergies, allowing effective symptom management.

Interestingly, both allergies and the common cold can result in a sinus infection. A sinus infection, or sinusitis, is an inflammation or swelling of the tissue lining your sinuses (air-filled spaces in your skull that surround your nasal cavity). Sinus infections can be caused by viral or bacterial infections, allergies, or other factors that disrupt the normal drainage of mucus from your sinuses. This occurrence results in symptoms such as nasal congestion, facial pain or pressure, and discharge. [7]

Therefore, it is crucial to know how to combat your allergy or cold symptoms and make use of treatment options where necessary to avoid a sinus infection.

What Can I Do If I Have Symptoms of a Cold?

Combatting a cold requires a multifaceted approach to alleviate your symptoms and shorten the duration of your infection.

Rest and Hydration:

Adequate rest allows your body to focus on fighting the virus while staying hydrated helps thin mucus and soothe your sore throat. [8]

Over-the-Counter Medications:

Pain relievers like ibuprofen can alleviate your fever and body aches, while decongestants and expectorants can target nasal congestion and cough. [8]

Warm Saltwater Gargle:

If you suffer from respiratory infections, like the common cold, relieve your sore throat by gargling with warm saltwater, reducing inflammation and providing temporary relief. [8]

Drink Ginger Tea:

Ginger has demonstrated efficacy as a natural remedy against the common cold due to its anti-inflammatory and antiviral properties, which help alleviate symptoms and support the immune system. [9]

What Helps to Relieve Seasonal Allergy Symptoms?

Do you want to nip your allergy in the bud? We’ve got you covered. When it comes to combating seasonal allergies, a proactive approach and knowing about home remedies to managing annoying allergy symptoms is critical.

Allergy season mainly occurs during spring, summer, and fall, even though, depending on your geographical location, the peak allergy season for your allergen may vary.

Identify and Avoid Triggers:

Recognize the specific allergens causing your symptoms and take steps to minimize exposure where possible. This may include keeping your windows closed during high pollen seasons or using air purifiers to reduce indoor allergens. If it is dry and windy outside, it is best to stay indoors. Rain helps clear pollen from the air, so take a nice long stroll after it has rained. [10]

Over-the-Counter Antihistamines:

Non-drowsy antihistamines can provide effective relief from allergy symptoms by blocking histamine, an essential hormone in the immune response that is triggering your allergy symptoms. [10]

Nasal Steroids:

These prescription or over-the-counter nasal sprays help reduce inflammation in the nasal passages, alleviating symptoms like congestion, a runny nose, and nasal itching. [10]

Immunotherapy:

For those with persistent or severe allergies, allergen immunotherapy, commonly known as allergy shots, can desensitize your immune system over time, providing long-term relief. [10]

Humidifier Use:

Adding moisture to the air with a humidifier can soothe your irritated nasal cavities and a scratchy throat. [10]

Maintain a Clean Home:

Year-round allergens like dust mites and pet dander can cause you trouble on a daily basis. Clean and dust your home regularly to minimize exposure to allergens that are present at all times of the year. [10]

Now, you know about the difference between a cold and allergies, and we hope this article will be a helpful resource for you the next time you experience symptoms that could be either. Distinguishing between a cold vs. allergy is crucial for effective and targeted symptom management, as treatment and preventive measures differ significantly.