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Understanding Allergy Symptoms

Allergies kick in when your immune system overreacts to normally harmless substances called allergens. Your body releases a chemical called histamine, and you start to experience a variety of symptoms.

1. Itchy, watery eyes

Many allergens are airborne and come into direct contact with your eyes. That's why over 80% of people with allergies experience itchy, watery, teary eyes.

2. Runny nose

When allergens enter your nose, the membrane swells and presses a fluid out of small blood vessels in your nasal passages – typically a thin, clear liquid.

3. Sneezing

Your body's reaction to histamine includes itchiness and swelling inside your nose and throat. As a result, your brain tells your chest to contract and you start sneezing.

4. Itchy nose or throat

Itchy nasal passages are also a reaction to a lot of histamine in your system.

5. Sinus congestion

If your allergies include upper respiratory symptoms – sneezing, itchy and runny nose – your sinuses may become swollen and blocked.

ZYRTEC® gives you powerful relief from these allergy symptoms. If you have a blocked nose, ZYRTEC®-D will also help to alleviate nasal and sinus congestion.