Understanding Allergy Symptoms

Allergies kick in when your immune system overreacts to normally harmless substances called allergens. Your body releases many chemicals, one of which is called histamine. Histamine is the most abundantly released chemical and is responsible for causing most of your symptoms.

A sick South Asian woman sitting with a napkin close to her nose from allergy.

1. Itchy, watery eyes

Airborne allergens come into direct contact with your eyes. Over 80% of people with allergies experience this symptom.

2. Runny nose

When allergens enter your nose, your immune system releases a chemical that can make the blood vessels in your nose swell and cause them to expand. This allows the fluid to come out into the nose as a thin, clear, watery liquid.

3. Sneezing

Your body’s reaction to histamine includes itchiness and swelling inside your nose and throat. As a result, there is irritation of your nasal passage and some obstruction in your ability to breathe through your nose. This will trigger nerves in your nose to send a signal to your brain to which it responds with your sneeze reflex to help clear the irritation or obstruction.

4. Itchy nose or throat

Itchy nasal passages are also a reaction to the release of histamine triggered by an allergen in your system. Histamine interacts with the nerves in the nasal passage which reacts by causing the itching.

5. Sinus congestion

If your allergies include upper respiratory symptoms – sneezing, itchy and runny nose – your sinuses may become swollen and blocked as the nasal passage branches into your sinuses, which make them prone to the same reaction as your nasal passage.


Cold Vs. Allergy Symptoms

Allergies are often confused with cold. The difference in symptoms between cold and allergies can be subtle, but the following highlights the primary differences between the two: 1

 Symptom             Cold                                 Allergies                
Fever Sometimes Unlikely
Body Aches Sometimes Unlikely
Itchy Eyes Unlikely Yes
Sneezing Yes Yes
Congestion Yes Yes
Runny Nose Yes Yes
Mucus Thick, Yellow/Green Thin, clear

While a cold may last anywhere from 7 – 10 days, allergies tend to last much longer and throughout the season, or when constantly exposed to certain environments. Cold symptoms also appear more gradually compared to allergies where symptoms may suddenly flare up.

Dealing with confusing symptoms can be problematic, especially when you are trying to figure out the most appropriate treatment for your condition. If you are still unsure of your symptoms, consult your doctor or local healthcare practitioner for further advice. When taking OTC medications, always follow the instructions directed on the label and never take the medications for longer than prescribed.

Speak to your doctor or pharmacist. To be sure this product is right for you, always read and follow the label.


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