Health
Fact-checked

At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What are the Differences Between Allergies and a Cold?

Tricia Christensen
Tricia Christensen
Tricia Christensen
Tricia Christensen

Telling the differences between allergies and a cold is often a matter of understanding the symptoms of each. From a purely medical standpoint, allergies are a histamine response to things a person is allergic to, like pollens, mold, or dust mites. Colds, on the other hand, are the body’s response to dealing with a virus, typically a set of hundreds of rhinoviruses. There may be similarities between the two, but the differences can help a sufferer understand how to best address these separate conditions.

One of the early differences between allergies and a cold is the onset of symptoms. Allergies generally occur quickly, with all symptoms, like runny nose, itchy eyes, and scratchy throat, happening within a few hours of exposure. Cold symptoms tend to develop over a few days. A person might one day have a slightly congested nose and a slightly scratchy throat, but it may take several days before these symptoms progress to a full-blown cold.

Colds usually involve the throat and symptoms last several days.
Colds usually involve the throat and symptoms last several days.

Nasal discharge can also signify one of the differences between the two conditions. Allergic nasal response tends to have a discharge that is clear or white, and fairly thin. In the early days of a cold, discharge is thicker, sometimes so thick it is difficult to clear the nose by blowing it. No matter the cause, continued nasal discharge that becomes thick brown, dark yellow, or green might indicate a sinus infection.

Allergy symptoms typically come on very quickly.
Allergy symptoms typically come on very quickly.

How long a person continues to have symptoms also can help determine if it is an allergy or a cold. Generally, a cold lasts for seven to 14 days. Allergies, especially seasonal ones, can last for three weeks to several months. Colds can occur at any time of year, but allergies to pollen are likely to occur most often in spring and fall.

Both allergies and colds can cause feelings of fatigue, headaches, sneezing, coughing and asthma. One of the differences is that colds from certain viruses may also cause slight fevers. Allergies, though they are often called hay fever, rarely cause fevers unless the sufferer has a sinus infection.

Allergies rarely cause fevers, but a cold might.
Allergies rarely cause fevers, but a cold might.

People might also notice that they can tell the two apart by the medications that relieve the symptoms. Decongestants can be used for either allergies or a cold, but antihistamines are designed for allergies. The allergy symptoms are likely to resolve quickly, and may not return until the sufferer is re-exposed to the allergens. An antihistamine may provide minor relief to cold symptoms, but it will not eliminate them.

Antihistamines are designed to treat symptoms caused by allergies.
Antihistamines are designed to treat symptoms caused by allergies.

Though similarities exist in these two conditions, recognizing the differences between allergies and a cold can help in preventing allergies. People who are prone to seasonal allergies often find that antihistamines can help them almost completely eliminate the symptoms. It’s much harder to prevent a cold, though good hand washing practices certainly help.

Tricia Christensen
Tricia Christensen

Tricia has a Literature degree from Sonoma State University and has been a frequent WiseGEEK contributor for many years. She is especially passionate about reading and writing, although her other interests include medicine, art, film, history, politics, ethics, and religion. Tricia lives in Northern California and is currently working on her first novel.

Learn more...
Tricia Christensen
Tricia Christensen

Tricia has a Literature degree from Sonoma State University and has been a frequent WiseGEEK contributor for many years. She is especially passionate about reading and writing, although her other interests include medicine, art, film, history, politics, ethics, and religion. Tricia lives in Northern California and is currently working on her first novel.

Learn more...

Discussion Comments

write79

I always heard that if nasal discharge is clear, then it's allergies. But if it's not clear, then it's a cold.

But recently I took my son to the doctor, and the doctor said that clear nasal discharge can be a symptom of allergies or a cold.

I don't think I'll ever be able to tell the difference!

roxytalks

The only way I can ever tell if I have a cold or am just suffering from a bout of allergies, is by using allergy remedies. If I take a medication specifically for allergies, and feel better, than I assume that's what the problem was.

It doesn't work for me though, by taking cold remedies. I've found that those medications will make me feel a little better if I have a cold, but also if I have allergies.

reader888

I'm always trying to determine whether my kids are suffering from a cold or allergies, and it is very hard to tell the difference. They rarely ever get fevers, so I can't really use that as a determining factor.

Even when I take them to the doctor, I am usually told that it could be either one. It's very frustrating to not be able to tell the difference. I don't want my children to get other children sick, yet I don't want my children to have to sit around the house doing nothing, when in fact all they have are allergies, which aren't contagious.

It would be nice if there was a simple do-it-yourself test that could easily and painlessly tell the difference between a cold and allergies.

Post your comments
Login:
Forgot password?
Register:
    • Colds usually involve the throat and symptoms last several days.
      By: Maxim Vlasenko
      Colds usually involve the throat and symptoms last several days.
    • Allergy symptoms typically come on very quickly.
      By: luna
      Allergy symptoms typically come on very quickly.
    • Allergies rarely cause fevers, but a cold might.
      By: evgenyatamanenko
      Allergies rarely cause fevers, but a cold might.
    • Antihistamines are designed to treat symptoms caused by allergies.
      By: Wellford Tiller
      Antihistamines are designed to treat symptoms caused by allergies.
    • A person may catch a cold by having a weakened immune system caused by a lack of rest.
      By: psd photography
      A person may catch a cold by having a weakened immune system caused by a lack of rest.
    • Colds are more likely to occur during winter months, while allergies are more common during spring and summer.
      By: jinga80
      Colds are more likely to occur during winter months, while allergies are more common during spring and summer.