Post-nasal drip is caused by the excessive production or accumulation of mucus that drips down the back of the nose and throat. Common causes include:
- Allergies (allergic rhinitis): Exposure to allergens like pollen, dust, and pet dander triggers inflammation and increased mucus production
- Viral infections: Colds, flu, and other viral infections cause inflammation of the nasal passages and sinuses, leading to mucus buildup
- Sinus infections (sinusitis): Inflammation or infection of the sinuses increases mucus production and drainage
- Non-allergic rhinitis: This includes irritants such as cigarette smoke, chemical fumes, perfumes, and dry or cold air that irritate the nasal lining
- Gastroesophageal reflux disease (GERD): Acid reflux can irritate the throat and nasal passages, contributing to post-nasal drip
- Structural nasal problems: Deviated septum, nasal polyps, or enlarged turbinates can disrupt normal mucus drainage and cause post-nasal drip
- Medications: Some drugs, including birth control pills and blood pressure medications, can thicken mucus or dry mucous membranes, leading to symptoms
- Other causes: Pregnancy, certain foods (like spicy foods), sensitivity to bright lights, and foreign objects in the nose (especially in children) can also cause post-nasal drip
In summary, post-nasal drip results from increased mucus production or impaired drainage due to infections, allergies, irritants, structural issues, or other underlying conditions
