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Frequent tearing can be caused by various factors, including dust allergies, allergic conjunctivitis, or nasolacrimal duct obstruction. Each cause has different symptoms and treatments. This article will help explain the differences and basic care methods to understand the causes of tearing and appropriate treatments.
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<h2>Common Causes of ‘Tearing’</h2>
<ul>
<li style="font-weight: 500;">
<h4>Dust Allergy and Allergic Conjunctivitis</h4>
Usually caused by the body&#8217;s reaction to allergens such as dust, smoke, pollen, or dust mites, resulting in itchy eyes, burning sensation, tearing, red eyes, and itching. Symptoms often occur in both eyes simultaneously and may be accompanied by nasal symptoms such as nasal congestion and difficulty breathing.</li>
</ul>
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<ul>
<li style="font-weight: 500;">
<h4>Nasolacrimal Duct Obstruction</h4>
This condition occurs when the nasolacrimal duct, which drains tears from the eyes to the nasal cavity, becomes blocked, preventing normal tear drainage. This causes constant tearing or overflow, unrelated to sadness or dry eyes. It can occur from infancy to adulthood.</li>
</ul>
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<h2>Comparison of Symptoms Between Allergies and Nasolacrimal Duct Obstruction</h2>
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<table style="width: 100%; height: 255px;">
<tbody>
<tr style="height: 24px;">
<td style="height: 24px; width: 21.1747%; text-align: center;">Symptoms</td>
<td style="height: 24px; width: 34.7759%; text-align: center;">Dust Allergy/Allergic Conjunctivitis</td>
<td style="height: 24px; width: 43.5343%; text-align: center;">Nasolacrimal Duct Obstruction</td>
</tr>
<tr style="height: 183px;">
<td style="height: 183px; width: 21.1747%; text-align: center;">Eye Symptoms</td>
<td style="height: 183px; width: 34.7759%;">Tearing accompanied by itchy eyes and red eyes</td>
<td style="height: 183px; width: 43.5343%;">
<ul>
<li style="font-weight: 500;">Constant tearing, usually one or both eyes</li>
<li style="font-weight: 500;">Some cases have red eyes or sticky discharge</li>
<li style="font-weight: 500;">Presence of crusts or pus in some cases</li>
<li style="font-weight: 500;">A lump near the inner corner of the eye</li>
<li style="font-weight: 500;">Infection leading to dacryocystitis</li>
</ul>
</td>
</tr>
<tr style="height: 24px;">
<td style="height: 24px; width: 21.1747%; text-align: center;">Symptom Consistency</td>
<td style="height: 24px; width: 34.7759%;">Intermittent, depending on allergen exposure</td>
<td style="height: 24px; width: 43.5343%;">Constant tearing, does not resolve on its own, may have recurrent infections</td>
</tr>
<tr style="height: 24px;">
<td style="height: 24px; width: 21.1747%; text-align: center;">Cause of Symptoms</td>
<td style="height: 24px; width: 34.7759%;">Usually caused by allergens such as dust and smoke</td>
<td style="height: 24px; width: 43.5343%;">Caused by blockage of the nasolacrimal duct or fibrosis in the tear drainage pathway</td>
</tr>
</tbody>
</table>
<h2></h2>
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<h2>Causes and Risk Factors of Nasolacrimal Duct Obstruction</h2>
&nbsp;
<h2>In Newborns</h2>
Nasolacrimal duct obstruction in infants is mostly caused by a thin membrane blocking Hasner’s valve (the end of the nasolacrimal duct before it opens into the nasal cavity).
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This condition occurs in about 5–10% of newborns and is generally not severe because the membrane can open naturally as the infant grows.
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Most children recover within the first year of life, but some cases that do not improve may require additional treatment such as lacrimal duct massage or medical procedures.
&nbsp;
<h2>In Adults</h2>
Nasolacrimal duct obstruction in adults is often associated with several factors such as:
&nbsp;
<ul>
<li style="font-weight: 500;">Chronic inflammation of the nasolacrimal duct or surrounding tissues causing thickening and narrowing</li>
<li style="font-weight: 500;">Injury from accidents around the nose or face, such as nasal bone fractures or scars compressing and blocking the tear duct pathway</li>
<li style="font-weight: 500;">Nasal cavity abnormalities such as tumors inside the nasal cavity or deviated septum, leading to abnormal tear drainage</li>
<li style="font-weight: 500;">Increasing age causing tissue degeneration and reduced flexibility of the nasolacrimal duct, leading to obstruction</li>
<li style="font-weight: 500;">Post-surgery or radiation therapy on the face</li>
</ul>
&nbsp;
<h2>Who is at Risk for ‘Nasolacrimal Duct Obstruction’</h2>
<ul>
<li style="font-weight: 500;">Newborn infants are at high risk of congenital nasolacrimal duct obstruction due to underdeveloped tear drainage ducts or membrane blockage.</li>
<li style="font-weight: 500;">Adults and elderly, especially those with a history of frequent eye or inner eye infections, chronic inflammation, or injury around the inner eye, may develop nasolacrimal duct obstruction.</li>
<li style="font-weight: 500;">Those with tumors near the inner eye or adjacent nasal cavity may experience nasolacrimal duct obstruction due to compression or tumor growth.</li>
<li style="font-weight: 500;">Individuals with chronic inflammation in the tear drainage system, such as chronic dacryocystitis, which can cause duct blockage.</li>
</ul>
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<h2>Care and Treatment</h2>
<ul>
<li style="font-weight: 500;">For dust allergies and allergic conjunctivitis, 
avoid allergens such as dust and dust mites, maintain cleanliness, and possibly use eye drops or antihistamines as directed by a doctor.</li>
</ul>
<ul>
<li style="font-weight: 500;">For nasolacrimal duct obstruction in children, lacrimal duct massage is recommended to reduce blockage and persistent tearing due to allergies.</li>
</ul>
<ul>
<li style="font-weight: 500;">In adults or chronic obstruction cases, treatment may involve dilation of the tear drainage duct or surgery, such as endoscopic dacryocystorhinostomy (DCR) to create a new tear drainage pathway without scarring.</li>
</ul>
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In summary, frequent tearing can result from various causes. Allergies and allergic conjunctivitis usually present with itching and red eyes, while nasolacrimal duct obstruction causes constant tearing without itching or allergy symptoms.
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Therefore, diagnosis by a specialist is important to receive appropriate treatment. If tearing is frequent, persistent, or accompanied by other abnormal symptoms, an ophthalmologist should be consulted for proper diagnosis and specialized treatment.

Frequent tearing doesn&#039;t always mean you&#039;re allergic to dust. Sometimes, it can be a warning sign of a blocked tear duct, a condition where tears can&#039;t drain properly. Learn about the causes and how to treat them before they become chronic in this article.

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Frequent tears may not be due to allergies, but rather a blocked tear duct!

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