Nasal Polyps: Symptoms, Types, Causes and Treatment

Nasal polyps are soft, painless, noncancerous growths that can develop in the lining of the nose or sinuses. While often overlooked, they can profoundly impact quality of life, causing symptoms that disrupt breathing, sleep, and even the sense of smell. In this article, we provide an in-depth exploration of nasal polyps, including their symptoms, types, underlying causes, and modern treatment options. Whether you are newly diagnosed or searching for advanced information, this guide synthesizes current scientific understanding to help you navigate this common but complex condition.

Symptoms of Nasal Polyps

Nasal polyps can go unnoticed in their early stages, but as they grow, they begin to interfere with normal nasal and sinus functions. Recognizing these symptoms is crucial for early diagnosis and effective management. Notably, nasal polyps often present differently from other sinus conditions, making awareness of their unique symptom profile essential for patients and clinicians alike.

Symptom	Description	Commonality	Source(s)
Congestion	Persistent nasal blockage or stuffiness	Most frequent	1 3 4 5
Rhinorrhea	Runny nose (anterior/posterior drip)	Very common	1 2 3 4
Hyposmia	Reduced sense of smell	Highly characteristic	2 3 4
Anosmia	Complete loss of smell	Severe cases	3 4
Facial Pressure	Sensation of fullness (not pain)	Common	1 3
Sneezing	Occasional, less prominent	Less common	3
Sleep Disturbance	Poor sleep due to symptoms	Noted frequently	4

Table 1: Key Symptoms

Symptom Breakdown

Nasal Congestion and Obstruction

The most commonly reported symptom, nasal congestion, can be severe and persistent. Patients often describe a constant feeling of blockage, making it difficult to breathe through the nose. This congestion is typically perennial, meaning it occurs year-round rather than in seasonal bouts 1 3 4.

Rhinorrhea (Runny Nose)

Polyps often cause a continuous runny nose, with both clear anterior (front) and posterior (dripping down the back of the throat) discharge. This symptom, known as rhinorrhea, can be bothersome and socially inconvenient, often requiring individuals to carry tissues at all times 2 3.

Loss or Reduction of Smell (Hyposmia/Anosmia)

A hallmark symptom of nasal polyps is a reduced or absent sense of smell. This can significantly impact daily life, from affecting the enjoyment of food to reducing awareness of environmental hazards. Studies show that hyposmia or anosmia is more strongly associated with nasal polyps than with other forms of chronic sinusitis 2 3 4.

Facial Pressure (Without Pain)

Patients often report a sense of fullness or pressure in the face, especially around the cheeks and eyes. Unlike sinusitis without polyps, frank facial pain and headaches are less common in polyp patients 2 3.

Sleep Disturbance and Quality of Life

The persistent symptoms of nasal polyps, especially congestion and reduced airflow, frequently disrupt sleep and diminish overall quality of life. Many report daytime fatigue and reduced productivity as a result 4.

Differentiating Symptoms

Importantly, while symptoms like congestion and rhinorrhea overlap with other nasal conditions, the combination of these with a reduced sense of smell and minimal facial pain helps distinguish nasal polyps from other sinus diseases 2.

Types of Nasal Polyps

Nasal polyps are not all the same. They can be classified based on their location, appearance, and, most importantly, their underlying histological and inflammatory patterns. Understanding these types can guide both diagnosis and treatment, especially as new therapies target specific forms of the disease.

Type	Key Feature	Prevalence/Clinical Note	Source(s)
Edematous/Eosinophilic	Swollen, eosinophil-rich tissue	85-90%; most common	7 9 8
Fibroinflammatory	Chronic inflammation, fibrosis	Less common	7 9
Glandular Hyperplastic	Increased seromucinous glands	Rare	7 9
Stromal Atypia	Abnormal stroma, rare	Very rare; consider neoplasm	7 9
Eosinophilic CRSwNP	High tissue eosinophils	Severe, recurrent	6 8 10
Neutrophilic CRSwNP	Dominated by neutrophils	Less severe, distinct	6
Mixed Inflammatory	Combination of cell types	Variable recurrence	6 10

Table 2: Types of Nasal Polyps

Histological Subtypes

Edematous/Eosinophilic (Allergic) Polyps

These are the classic, most frequent form. Characterized by pronounced tissue swelling (edema), abundant eosinophils (a type of white blood cell involved in allergic reactions), and a loose, gelatinous appearance. This type is strongly linked to type 2 inflammation and is seen in the majority of Western patients 7 8 9.

Fibroinflammatory Polyps

Marked by chronic inflammation and increased fibrous tissue, these polyps show metaplastic (changed) epithelium and are less responsive to typical anti-inflammatory treatments 7 9.

Glandular Hyperplastic Polyps

Rare, these polyps feature increased numbers of seromucinous glands. While structurally similar to edematous polyps, they have distinct glandular proliferation 7 9.

Polyps with Stromal Atypia

Extremely rare, these polyps display abnormal stromal (connective) tissue. Care must be taken to differentiate them from neoplastic (potentially cancerous) growths 7 9.

Inflammatory Phenotypes

Eosinophilic CRSwNP

Defined by high tissue eosinophil counts, these polyps are associated with more severe symptoms, higher rates of recurrence after surgery, and resistance to standard therapies. Eosinophilic CRSwNP is increasing worldwide and is particularly common in patients with asthma or aspirin-exacerbated respiratory disease 6 8 10.

Neutrophilic and Mixed Phenotypes

Some polyps are dominated by neutrophils or contain a mixture of immune cells. Neutrophil-rich polyps tend to be less severe and less likely to recur, while mixed inflammatory patterns have variable clinical outcomes 6 10.

Clinical Importance of Typing

Identifying the specific type and inflammatory profile of a nasal polyp is becoming increasingly important as targeted biological therapies become available. For example, patients with eosinophilic, type 2-high polyps are more likely to benefit from medications that block interleukins such as IL-4, IL-5, or IgE 10.

Causes of Nasal Polyps

The development of nasal polyps is a multifactorial process involving chronic inflammation, immune system dysfunction, and, in some cases, genetic and environmental influences. While the exact cause remains elusive, significant advances have been made in understanding the mechanisms that drive polyp formation.

Cause	Mechanism/Factor	Clinical Relevance	Source(s)
Chronic Inflammation	Persistent local immune response	Central to pathogenesis	1 3 12 13 14
Epithelial Barrier Dysfunction	Loss of mucosal integrity	Allows irritant/microbe entry	1 12 13
Type 2 Inflammation	Th2 cytokines (IL-4, IL-5, IL-13)	Drives eosinophilic polyps	8 10 12 13 19
Microbial Colonization	Bacteria/fungi in sinuses	Triggers/maintains inflammation	1 13 14
Genetic Factors	Cystic fibrosis, primary ciliary dyskinesia	Strong in children	3 9 14
Comorbid Conditions	Asthma, AERD, allergy	Increases risk/severity	1 3 4 14 18
Abnormal Fibrin Deposition	Impaired fibrinolysis, t-PA reduction	Maintains polyp edema	8 11

Table 3: Causes and Mechanisms of Nasal Polyps

Chronic Inflammation and Immune Dysregulation

Nasal polyps are fundamentally an inflammatory disease. Persistent activation of the immune system within the nasal and sinus mucosa leads to swelling, tissue remodeling, and polyp formation. This inflammation is often chronic, lasting months or even years 1 3 12 13.

Epithelial Barrier Dysfunction

A healthy nasal lining acts as a barrier to pathogens and irritants. In patients with polyps, this barrier is often compromised—due to either genetic factors or ongoing inflammation—allowing bacteria, viruses, and allergens to penetrate deeper tissues and perpetuate inflammation 1 12 13.

Type 2 (Th2) Inflammation

A specific immune pathway known as type 2 inflammation is central to most cases of nasal polyps, especially the eosinophilic subtype. Cytokines such as IL-4, IL-5, and IL-13, produced by T-helper cells and innate lymphoid cells, drive the recruitment and activation of eosinophils and mast cells. This leads to tissue swelling and the classic appearance of polyps 8 10 12 13 19.

Microbial Colonization

Chronic colonization by bacteria (such as Staphylococcus aureus) and, in some cases, fungi, can stimulate ongoing immune responses. Staphylococcal superantigens may amplify type 2 inflammation, particularly in patients predisposed to allergic reactions 1 3 13 14.

Genetic and Comorbid Factors

• Cystic Fibrosis: Children with nasal polyps should be evaluated for cystic fibrosis, a genetic condition that causes thick, sticky mucus and recurrent infections.
• Primary Ciliary Dyskinesia and Kartagener’s Syndrome: These rare disorders impair the normal movement of mucus, predisposing to chronic sinus disease and polyps 3 9 14.

Asthma, aspirin-exacerbated respiratory disease (AERD), and allergies are strongly associated with nasal polyps, both as risk factors and as indicators of more severe, treatment-resistant disease 1 3 4 14 18.

Abnormal Fibrin Deposition

An intriguing recent discovery is the role of impaired fibrinolysis—the body’s ability to break down clots—in maintaining the swollen, edematous state of polyps. Reduced expression of tissue plasminogen activator (t-PA), under the influence of type 2 cytokines, leads to excessive fibrin buildup and sustained edema in polyp tissue 8 11.

Treatment of Nasal Polyps

Managing nasal polyps is a dynamic process that balances symptom control, recurrence prevention, and minimizing side effects. Treatment options have expanded rapidly in recent years, with innovative therapies now available for severe or refractory cases.

Treatment	Approach/Medication	Use/Indication	Source(s)
Intranasal Steroids	Nasal sprays (e.g., mometasone)	First-line, reduces size/symptoms	3 4 14
Oral Steroids	Short courses for severe symptoms	Rapid reduction of polyp size	3 4 14
Surgery	Endoscopic sinus surgery	For obstruction or failed medical therapy	3 4 14 18
Biologics	Dupilumab, omalizumab, mepolizumab, benralizumab	Severe/refractory, type 2-high polyps	15 16 17 18 19
Aspirin Desensitization	For AERD patients	Reduces recurrence in select cases	3
Saline Irrigation	Nasal rinses	Adjunct for symptom relief	15
Antibiotics	For secondary infections	Adjunct, not for polyp management	15

Table 4: Treatment Options for Nasal Polyps

Medical Therapy

Intranasal Corticosteroids

These sprays are the cornerstone of therapy, shrinking polyps, reducing inflammation, and improving nasal airflow. They are well-tolerated and can be used long-term, although complete resolution is uncommon 3 4 14.

Oral Corticosteroids

Short-term oral steroids may be prescribed for severe symptoms or before surgery to rapidly reduce polyp size. Long-term use, however, is avoided due to significant side effects 3 4 14.

Saline Irrigation

Regular nasal rinsing helps clear mucus and reduce local inflammation, enhancing the effectiveness of other topical treatments 15.

Surgical Management

Surgery is reserved for patients who do not respond to medical therapy or whose polyps cause severe obstruction or recurrent infections. Functional endoscopic sinus surgery (FESS) removes polyps and opens sinus passages, improving symptoms and delivery of topical medications. Recurrence is common, emphasizing the need for ongoing medical therapy post-surgery 3 4 14 18.

Biologic Therapies

A revolution in treatment, biologic drugs target specific molecules driving type 2 inflammation:

• Dupilumab: Blocks IL-4/IL-13 pathways. Reduces polyp size, improves sense of smell, and decreases need for surgery and steroids 17 19.
• Mepolizumab: Targets IL-5. Reduces polyp burden and improves symptoms in severe, eosinophilic cases 15 17.
• Omalizumab: Anti-IgE antibody, effective in allergic and non-allergic polyps 17 19.
• Benralizumab: Depletes eosinophils, improving nasal blockage and reducing polyp size 16.

Biologics are generally reserved for patients with severe, recurrent, or steroid-dependent disease, particularly when type 2-high inflammation is confirmed 15 16 17 18 19.

Additional and Adjunct Approaches

• Aspirin Desensitization: For patients with AERD, this can reduce the need for surgery and improve symptoms 3.
• Antibiotics: Used only for treating secondary infections, not for the polyps themselves 15.

Monitoring and Long-Term Management

Given the high rate of recurrence, ongoing follow-up and maintenance therapy are essential. New algorithms and monitoring protocols are being developed to personalize treatment based on inflammatory phenotype, comorbidities, and response to therapy 18.

Conclusion

Nasal polyps are more than just a nuisance—they are a manifestation of complex, chronic inflammation with significant effects on quality of life. Thanks to advances in our understanding, both diagnosis and treatment are rapidly evolving.

Key points covered:

• Symptoms: Persistent nasal congestion, rhinorrhea, and especially reduced or lost sense of smell are hallmark features, with minimal facial pain distinguishing polyps from other sinus diseases.
• Types: Several histological and inflammatory types exist, with eosinophilic (type 2-high) polyps being most common and severe.
• Causes: Chronic inflammation, epithelial barrier dysfunction, type 2 cytokine activity, microbial colonization, and certain genetic factors all contribute to polyp formation.
• Treatment: Intranasal steroids remain first-line, with surgery and new biologic drugs offering hope for severe and refractory cases. Personalized, phenotype-driven therapy is increasingly important.

Understanding nasal polyps empowers patients and clinicians to navigate a wide array of treatments and improve quality of life in this challenging chronic disease.