What causes a foul-smelling odor from the nose, also known as rhinotorrhoea (runny nose) or ozena (atrophic rhinitis)?

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From the Guidelines

A smelly nose is typically caused by sinus infections, nasal polyps, foreign objects, or poor hygiene. Bacterial or fungal infections in the sinuses produce foul-smelling discharge as they multiply and create waste products 1. Nasal polyps can trap mucus and debris, leading to odor when they decompose 1. In children especially, foreign objects stuck in the nose can cause a distinctive smell as they irritate the nasal tissue and collect bacteria. Poor hygiene practices, like infrequent nose blowing or improper cleaning, allow mucus to accumulate and develop odor. Other causes include certain medications that alter nasal secretions, dental infections that connect to the nasal cavity, and systemic conditions like diabetes that affect body odors 1.

Some key points to consider in the diagnosis and management of a smelly nose include:

  • The use of nasal endoscopy to visualize the nasal cavity and sinuses 1
  • The importance of distinguishing between allergic and nonallergic rhinitis, as well as between acute and chronic sinusitis 1
  • The role of imaging techniques, such as CT scans, in confirming the diagnosis of sinusitis 1
  • The use of antibiotic or antifungal medications for infections, and removal of any foreign objects or polyps 1

Treatment depends on the cause but often includes:

  • Saline nasal rinses (using distilled water with 1/4 teaspoon salt and 1/4 teaspoon baking soda) 1
  • Antibiotic or antifungal medications for infections 1
  • Removal of any foreign objects or polyps 1 Maintaining good nasal hygiene by gently blowing your nose regularly and staying hydrated can help prevent most cases of nasal odor.

From the Research

Causes of a Smelly Nose

There are several potential causes of a smelly nose, including:

  • Nasal congestion, which can be caused by allergic rhinitis, common cold, or other conditions 2, 3, 4
  • Infections, such as sinusitis or rhinitis, which can cause a foul odor in the nose
  • Poor hygiene or nasal secretions, which can contribute to a smelly nose
  • Certain medications, such as pseudoephedrine, which can have side effects like dry mouth or nasal congestion 3, 5

Relationship Between Nasal Congestion and Smelly Nose

Nasal congestion can contribute to a smelly nose by:

  • Reducing the ability to smell, making it more difficult to detect odors
  • Increasing the production of mucus, which can harbor bacteria and cause a foul odor
  • Allowing bacteria to grow and multiply in the nasal passages, leading to a smelly nose

Treatment Options for Nasal Congestion

Treatment options for nasal congestion, which can help alleviate a smelly nose, include:

  • Antihistamines, such as desloratadine, which can help reduce nasal congestion and other symptoms of allergic rhinitis 2, 4
  • Decongestants, such as pseudoephedrine, which can help relieve nasal congestion and reduce the production of mucus 3, 5
  • Combination therapies, such as antihistamine-decongestant combinations, which can provide relief from multiple symptoms of the common cold or allergic rhinitis 6

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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