When the weather changes or seasons shift, many people experience a runny nose, nasal congestion, itchy eyes, and a sore throat. Often, they assume they have simply caught a cold and overlook the possibility that these may be allergy symptoms. Allergies and colds can produce similar symptoms, but distinguishing between them can help people choose the appropriate treatment.

Allergy symptoms include: a runny nose (usually with thin, clear discharge), sneezing, nasal congestion, wheezing, and itchy eyes, nose, or throat. Allergy symptoms may also include watery eyes and usually do not cause a fever.

Causes/Duration: These symptoms are commonly caused by exposure to allergens such as pollen, dust mites, mold, animal dander, and certain chemicals or other substances. Symptoms can continue as long as a person remains exposed to the allergen. Seasonal allergies are particularly common during periods when pollen levels are high.

Symptoms of a common cold caused by a virus can include: a runny or stuffy nose, sneezing, sore throat, cough, mild fever, headache, and feelings of tiredness or weakness. Nasal discharge may become thicker or change color during a cold, but the color of mucus alone cannot reliably distinguish a cold from an allergy.

Causes/Duration: Cold symptoms usually develop about 1–3 days after exposure to a respiratory virus and commonly improve within about 7–10 days, although a cough or other symptoms may last longer.

If symptoms are severe, persistent, repeatedly interfere with daily activities, or include significant difficulty breathing, medical advice should be sought.

作者：Michael Chiu，MWS，CI
Previously published in Ming Pao Daily News – Updated and Revised in 2026