Overview

Nasal congestion, commonly known as a stuffy nose, occurs when the tissues inside the nose become irritated, leading to inflammation, swelling, and increased mucus production. It can make breathing through the nose very difficult. While nasal congestion often resolves within a few days, persistent congestion lasting more than a week may indicate an infection and can lead to complications like sinusitis, nasal polyps, or middle ear infections if left untreated. Various factors can cause nasal congestion, including infections like colds, the flu, or sinusitis, as well as allergies. Airborne irritants, such as smoke, perfume, dust, and car exhaust, can also trigger these symptoms. In some cases, people experience chronic congestion without a known cause, a condition called nonallergic rhinitis or vasomotor rhinitis. Additionally, a runny nose may be caused by nasal polyps, any foreign object in the nose, tumours, or even migraine-like headaches. Understanding the different causes of nasal congestion is important for proper diagnosis and treatment.

Common causes of nasal congestion

Rhinitis 

Rhinitis is an inflammation of the mucous membrane lining of the nasal passage, leading to symptoms such as nasal congestion, sneezing, itching in the nose and palate, runny nose, and postnasal drainage. Rhinitis can be classified into three main categories: allergic, nonallergic, and infectious.¹

• Allergic rhinitis is specifically characterised by sneezing, nasal congestion, itching, and a runny nose. If an allergic condition is suspected, a skin prick test can be conducted to confirm the diagnosis. Management of mild cases often involves avoiding triggers and removing allergens, which can reduce symptom severity and minimise the need for medications. Oral antihistamines are commonly recommended for treating mild or occasional seasonal allergic rhinitis¹
• Nonallergic rhinitis has a variety of causes, which means treatment options can vary. For example, atrophic rhinitis is typically treated with nasal irrigation and cleaning, while gustatory rhinitis can be managed with pretreatment using ipratropium bromide. Understanding the type of rhinitis is crucial for effective treatment and symptom relief¹
• Infectious rhinitis is caused by agents like rhinoviruses and may sometimes be complicated by bacterial infections¹

Allergic rhinitis 

Allergic rhinitis is categorised based on its seasonality, nature, and association with certain environments.¹ It can be classified into:

• Seasonal allergic rhinitis: Typically triggered by pollen from trees, grass, or weed during specific times of the year
• Perennial allergic rhinitis: Caused by allergens that are present year-round, such as dust mites and animal dander
• Occupational rhinitis: Resulting from exposure to airborne particles in the workplace, this type includes both allergic reactions ( to animals or wood dust) and nonallergic responses ( to chemicals or irritants)

Infectious rhinitis

Infectious rhinitis can be caused by viruses, bacteria, or fungi, and is often referred to as infectious rhinosinusitis since both the nasal passages and sinuses are usually affected. It can be either acute or chronic.

Young children typically have 6 to 8 colds a year, which usually involve copious rhinorrhea. Viral rhinitis, or the common cold, generally resolves on its own within about 7 days. In contrast, bacterial rhinosinusitis lasts longer and presents with more severe symptoms. Diagnosis often involves endoscopy to visualise the nasal cavity and a CT scan of the sinuses can also be helpful for assessing chronic infections.²

Nasal polyposis

Nasal polyposis or polyps is a long-term inflammatory condition of the upper airway, where inflammatory cells, especially eosinophils, build up in the nasal passages. The exact cause is unclear, but it may be linked to chronic infections, sensitivity to aspirin, trapped pollutants, damage to the nasal lining, or allergies. About 4% of people are affected by this condition, which causes symptoms like a blocked nose, nasal discharge, and a reduced sense of smell. The congestion in nasal polyposis is due to swelling caused by inflammation, similar to what happens in conditions like allergic rhinitis. Research shows that people with nasal polyposis have high levels of certain inflammatory substances, which contribute to the swelling and damage in the nasal passages.³

Deviated nasal septum

Structural problems, like a deviated nasal septum, are common causes of nasal congestion. A deviated septum can cause constant stuffiness on one side of the nose or congestion that changes over time. Patients might have a history of nose injury. During an exam, doctors often see a bend in the septum, and the turbinates on the opposite side may be enlarged. Any issue with the nasal valve can also lead to nasal blockage.²

Medication-related

Drug-induced rhinitis, especially rhinitis medicamentosa, happens when you use nasal decongestant spray too much. This can lead to worse congestion after the medication wears off. Other drugs that can cause similar problems include aspirin, non-steroidal anti-inflammatory drugs (NSAIDs)), beta-blockers (pills and eye drops), bromocriptine, estrogens, birth control pills, and other certain medications.²

The severity of rhinitis medicamentosa does not always depend on how often the decongestant is used. Some studies suggest that preservatives in these sprays, like benzalkonium, may also make the condition worse.²

Sleep position

During the day, it's hard to breathe through the nose due to higher airflow resistance than the mouth. At night, when the muscles in the mouth and throat relax, breathing through the mouth becomes tougher, which can make the airway collapse more likely. The nose is more stable in its resistance, so it's usually better for breathing while sleeping. However, nasal congestion can get worse at night because of body position, making it feel more blocked. Research shows that having a blocked nose is linked to snoring. People who snore often have nasal congestion and other allergy problems at night.²

Hormonal changes

Endocrine and metabolic causes of nasal congestion include hormonal changes, such as those during pregnancy and puberty, which can lead to nasal swelling and blockage. Additionally, hypothyroidism may also be linked to rhinitis symptoms.²

Diagnostic approaches

Healthcare providers diagnose nasal congestion by evaluating your symptoms and examining your nose, ears, and throat. They may also perform additional tests to rule out other causes:

• Throat culture to check for bacteria in your throat using a cotton swab
• CT scan may be ordered to check for any obstructions in your nose
• Nasal endoscopy: A special camera may be used to look inside your nose

Treatment options

Healthcare providers treat nasal congestion based on its cause. For instance, if your congestion is due to an allergy to cats, it's a type of allergic rhinitis. Avoiding cats and using medication can help ease your symptoms. For nonallergic rhinitis, managing the condition involves identifying what triggers your congestion and using appropriate treatments. 

Here are some treatment options depending on the type of rhinitis:

Nonallergic rhinitis

• Saline spray to keep the nose moist and help in clearing out mucus
• Antihistamines can calm your immune system’s response to irritants
• Corticosteroid nasal spray can reduce inflammation in nasal passages
• Ipratropium bromide spray helps with a runny nose

Allergic rhinitis

• Antihistamines can be used to soothe inflamed nasal tissues
• Corticosteroid nasal spray to reduce inflammation caused by allergies
• Decongestant nasal spray relieves a stuffy nose but should be used for no more than three days to avoid worsening congestion
• Anticholinergic nasal spray can reduce mucus production

How to manage nasal congestion

To manage nasal congestion effectively, follow a step-by-step approach:⁴

• Diagnosis by a physician, identifying what is causing the congestion
• Patient education and monitoring: teach the patient, their family, and caregivers about the condition and treatment goals. Tell any concerns and discuss treatment options and side effects
• Avoid environmental triggers: Try to avoid things that worsen the congestion, such as allergens (pollen, dust mites, animal dander), irritants (smoke, strong smells), and infections
• Pharmacotherapy: use medications to help manage the symptoms

Summary

Nasal congestion isn't a disease on its own but rather a symptom of other conditions that obstruct the nasal passageway. It is particularly common in cases of allergic rhinitis, and nasal polyposis, where inflammation of the nasal mucosa plays a key role. Due to its prevalence and the discomfort it causes, nasal congestion is a frequent complaint in primary care. Typically, nasal congestion resolves within a few days, but if it persists for a week or longer, it may be signalling an underlying infection. Without proper treatment, prolonged congestion can lead to complications such as sinusitis, the formation of nasal polyps, or ear infections. Proper diagnosis and treatment of nasal congestion are essential for achieving a positive outcome. Identifying the underlying cause, whether it's an infection, allergy, or other condition, is the first step. Effective management may include medications, such as antihistamines or decongestants, and lifestyle changes to avoid triggers. Timely and appropriate treatment helps relieve symptoms, prevents complications, and improves overall quality of life.