Stuffy and runny noses come for us all. But if you haven’t been recently exposed to, say, a nose-blowing neighbor on an airplane or a shedding cat, it can be challenging to determine whether you’re dealing with a common cold or allergies.
Meng Chen, M.D., a board-certified allergist and immunologist and clinical assistant professor in the department of internal medicine at Stanford University School of Medicine, says she commonly hears from patients that it can be hard to tell the difference between the two, because many of the symptoms overlap. There’s a scientific reason for those similarities, says Purvi Parikh, M.D., a board-certified allergist and immunologist at NYU Langone Health in New York City. “Your body and immune system can react the same way to different invaders, so a virus can trigger the same response in your nose, throat, ears, and eyes as an allergen,” she says.
Fortunately — with the help of a doctor — you can figure out what’s causing your symptoms. Ahead, the experts share how they go about diagnosing patients with these everyday illnesses.
What are some of the symptoms of both allergies and colds?
Allergies can trigger a variety of symptoms, including watery and itchy eyes, sneezing, and a runny or congested nose, according to Chen. Someone with allergies may also have asthma-like symptoms, like coughing. Cold symptoms can be similar, including a congested and runny nose, sneezing, and coughing.
To add to the confusion, many people feel run down and sick when they have allergies. “Allergy symptoms seem to mimic cold symptoms because they are both a state of inflammation in the body, which can be very taxing,” she says.
Some of the symptoms do overlap, but typically, colds and allergies have their own tempo and time frame. “Quick onset of symptoms with environmental exposures, such as pets or pollen, are characteristic of allergies. Colds tend to come on a bit slower,” says Ralph Strauss, M.D., a board-certified allergist and immunologist at Strauss Allergy & Asthma in Westbury and Commack, New York.
Though they come on rapidly, allergies can last weeks, months, and can be seasonal, depending on the allergen in question. Though they can come on fast (and sometimes resolve quickly if the allergen is removed), allergies can also last weeks. For example, if you’re allergic to cats, you might have acute and immediate allergy symptoms after you’ve been spending time with one — but Chen says those symptoms usually dissipate within a few hours of leaving the allergy-inducing environment. Pollen, meanwhile, can cause symptoms throughout the season. However, she says, there are also year-round allergies, like dust mites.
How can you tell if you have a cold?
If you have a common cold, you’ll probably have symptoms that aren’t associated with allergies in addition to the allergy-like symptoms. Cara Connors, M.D., a board-certified family medicine physician with the University of Tennessee Medical Center in Alcoa, Tennessee, says a cold can cause body aches and a severe sore throat, which don’t usually occur with allergies. Parikh also cites headaches, fatigue, and body aches as more typical cold symptoms. Allergies, meanwhile, might leave you feeling itchy.