What causes loss of smell?

Under normal circumstances, loss of smell may be caused by nasal foreign bodies, upper respiratory tract infections, chronic rhinitis, allergic rhinitis, sinusitis, or other conditions. Patients should promptly visit a正规 hospital to determine the underlying cause and receive appropriate treatment. Specific analyses are as follows:

1. Nasal Foreign Body

If a foreign object—such as peanuts, animal hair, or tissue paper—is lodged in the nasal cavity, it can block odor molecules from entering, leading to reduced or lost sense of smell. In such cases, rinsing the nasal cavity with saline solution may help remove the object. If self-cleaning is ineffective, medical assistance should be sought, where a doctor can use specialized instruments to safely remove the foreign body.

2. Upper Respiratory Tract Infection

When nasal mucosa becomes infected by viruses or bacteria, swelling and congestion may occur, impairing the normal function of olfactory nerves. Additionally, colds can increase nasal secretions, further blocking odor molecules. In these cases, patients may take medications such as acetaminophen tablets, ibuprofen tablets, or compound licorice tablets under medical guidance. Applying a warm, moist towel to the nasal area may also help alleviate symptoms of smell loss.

3. Chronic Rhinitis

In patients with chronic rhinitis, enlarged nasal turbinates or blockage of the olfactory cleft may prevent air from reaching the olfactory region, or olfactory cells may become impaired, resulting in smell dysfunction. Such patients may follow medical advice to use medications like levocabastine hydrochloride nasal spray, budesonide inhalation aerosol, or mometasone furoate nasal spray to relieve symptoms.

4. Allergic Rhinitis

Patients with allergic rhinitis develop non-infectious inflammation of the nasal mucosa upon exposure to allergens, causing mucosal edema that interferes with smell, leading to an inability to detect odors. These individuals can, under a doctor’s guidance, use medications such as loratadine tablets, cetirizine hydrochloride tablets, or azelastine hydrochloride nasal spray for treatment.

5. Sinusitis

Sinusitis often results from upper respiratory tract infections, causing nasal mucosal congestion, swelling, and increased inflammatory secretions, which may lead to diminished or lost smell. Some patients may also experience nasal congestion, purulent nasal discharge, and headaches. In such cases, patients may follow medical advice to take medications such as metronidazole tablets, tinidazole tablets, or Tongqiao Biyan tablets.

Besides the above relatively common causes, nasopharyngeal carcinoma can also present with similar symptoms. Given the complexity of possible conditions, it is recommended to promptly visit a hospital for comprehensive examinations to identify the exact cause and initiate timely treatment, avoiding delays in care.