What’s the difference between allergies and colds?

Chief, Allergy/Immunology
Lyndall Harrison, MD
Kelsey-Seybold Clinic













A lot of people have asked me how to tell the difference between allergies and colds.

Well, it can sometimes be difficult to tell the difference especially during a pollen season, such as we have in Houston, while, at the same time, we can still have cold viruses in circulation in April, May, and into summer.

An old rule of thumb is that if you have a runny nose with clear discharge combined with sneezing without fever it’s usually an allergic reaction.


Allergies can develop at any age and may change over the course of a person’s life – they can be insignificant, intermittently bothersome, create long-lasting misery, or, for some people, subside as years go by.

There are all kinds of allergies. There are allergic reactions involving the eyes, nose, and throat – that can lead to rhinitis and sinusitis – as  well as skin allergies, food allergies, drug allergies, insect sting allergies, and even latex allergies.

Currently, the top allergens in our area are from oak, sycamore, and mulberry trees. Patients having reactions to these are mainly dealing with rhinitis, sinusitis, and skin allergies caused by the surge in pollen and spores.

Oaks are a particularly large genus, commonly found in residential areas, as well as parks, and remote forests.

Later on, lots of pollen and mold spores fill our air in late summer and early fall, but the most prominent are the weeds, especially ragweed. It blooms in most of the country, but earlier in the year and farther north than where we are.

What should people do if suffering from allergies?

My short answer is there are three basic steps.

First, identify the causative allergen and attempt to avoid exposure. This can be simple and effective in some cases, such as removing a pet from the home. In most cases, however, it’s almost impossible to completely avoid your allergens.

Second, as physicians, we have access to a variety of appropriate medications. Typically, these are for a quick-acting treatment on an as-needed basis. For example, a prescription steroid nose spray could be considered a quick acting, as-needed antihistamine treatment for timely relief.And third, if a patient isn’t responding well to medications, we may consider an allergy immunotherapy injection program known simply as “allergy shots,” which may be the best treatment option offering long-term relief.

How can you reduce allergic reactions?

On a non-rainy spring day, the pollen counts are usually highest in the morning. So yard work in the evening hours might reduce your exposure. I advise patients to shower, shampoo, and change clothes immediately after coming back indoors.

Living as we do in southeast Texas with our usually mild climate, we’re exposed to high levels of allergens throughout the year. Anyone suffering from allergies and seeking relief may want to consider seeing one of our Allergy and Immunology specialists at Kelsey-Seybold for a medical evaluation.

We believe the key to successful treatment of allergic conditions begins with a good doctor-patient communication followed by treatment based on sound, scientifically proved evidence.

Dr. Harrison is a board-certified physician caring for patients – including children – at multiple Kelsey-Seybold Clinic locations across Greater Houston.

Learn more at kelsey-seybold.com.

Author Lyndall Harrison, MD

Published May 8, 2023