Can Smell Return After Chronic Sinusitis With Nasal Polyps?

Losing your sense of smell (anosmia) or having it significantly reduced (hyposmia) is one of the most frustrating symptoms of chronic rhinosinusitis with nasal polyps (CRSwNP). The good news is that medical and surgical treatments often improve your ability to smell. However, the amount and durability of recovery vary from person to person. While many experience significant improvement, normal or permanent recovery cannot be guaranteed.

It is also important to note that while people often say they have lost their sense of “taste,” CRSwNP usually takes away your ability to perceive flavor (which relies heavily on smell). Your basic taste functions on the tongue (sweet, salty, sour, bitter, umami) typically remain intact.

Ruling Out Other Causes and Staying Safe

Because complete anosmia can be dangerous, it is critical to use practical safety measures at home: rely on working smoke and carbon monoxide detectors, and check food freshness by expiration dates and food thermometers rather than relying on your nose.

Additionally, before assuming your smell loss is entirely due to polyps, a doctor should examine you to rule out other causes, such as a recent viral infection (like COVID-19), head trauma, medication side effects, or neurologic conditions. A clinical exam, nasal endoscopy, and validated smell tests (like the UPSIT or Sniffin’ Sticks) can help objectively measure your baseline smell and confirm the cause.

How CRSwNP Affects Your Smell

When you have chronic ethmoidal sinusitis with polyps, your sense of smell is typically impacted in a “mixed” way ^[1][2]:

1. Physical Blockage (Conductive Loss): Nasal polyps and swelling physically block airflow. Odor molecules simply cannot reach the olfactory cleft—the high, narrow area inside your nose where smell receptors live.
2. Inflammatory Dysfunction: CRSwNP is frequently driven by Type 2 inflammation, an overactive immune response involving specialized cells (like eosinophils) and inflammatory proteins ^[3]. This local inflammation doesn’t just block odors; it creates a toxic environment that suppresses how the olfactory tissue detects and transmits smell signals ^[4].

An examination cannot always determine the exact split between physical blockage and inflammatory dysfunction, which is why treatment often requires a step-by-step approach.

Step-by-Step Treatment Options

Treatment typically begins with foundational care: daily large-volume saline sinus rinses and correctly used intranasal corticosteroid sprays. If these do not restore your smell, your doctor may discuss other options.

Oral Corticosteroids

Short courses of oral steroids (such as prednisone) can rapidly reduce inflammation. In one prospective study, about 57% of patients experienced an objective improvement in their sense of smell after a short course ^[5].

• The Reality: While oral steroids work quickly, the benefits typically fade within 3 to 6 months after stopping the medication ^[6]. A short trial is sometimes used by clinicians to gauge if your smell can respond to medical therapy, but it is not a standalone diagnostic test.
• Safety: Even short courses can cause insomnia, mood changes, and elevated blood pressure or blood sugar. Repeated courses carry severe cumulative risks, including bone density loss and immune suppression. You should never self-start or repeatedly request oral steroids.

Functional Endoscopic Sinus Surgery (FESS)

FESS physically removes the polyps to clear the obstruction. Research shows that roughly 50% to 73% of patients in specific CRSwNP cohorts report an improvement in their sense of smell after surgery ^[7][8].

• The Reality: Smell may temporarily be worse immediately after surgery due to swelling and crusting. While some notice early improvement in 2 to 4 weeks, true recovery can take longer. Furthermore, surgery does not cure the underlying inflammation. In one long-term study, up to 79% of severe cases saw polyps return within 12 years, often causing smell to decline again ^[9].
• Safety & Maintenance: FESS carries uncommon but serious risks, including bleeding, infection, and very rarely, vision injury or cerebrospinal fluid leaks. Following surgery, ongoing maintenance therapy (like saline irrigations and topical steroids) is commonly recommended by surgeons to delay recurrence.

Biologic Medications

For patients with severe bilateral CRSwNP that remains uncontrolled despite appropriate topical treatments (often with prior surgery or a history of needing oral steroids), biologic medications are an option. These injections target the specific immune pathways driving the disease.

• The Options: Dupilumab targets the IL-4 and IL-13 pathways, mepolizumab targets IL-5, and omalizumab targets IgE ^[10][11][12].
• The Reality: Dupilumab currently has the most established data for smell improvement. In one major trial grouping, patients reported subjective smell improvements as early as day 3, and the proportion of patients with complete anosmia dropped from about 81% down to 28.5% over 24 weeks ^[12][13]. However, because there are no direct head-to-head trials comparing all these drugs against each other for smell, selection depends heavily on your specific disease profile (such as co-existing asthma), insurance coverage, and doctor preference.
• Safety & Maintenance: Biologics control inflammation but do not cure the disease; symptoms generally return if you stop taking them. They involve high costs, ongoing injections, and potential side effects like injection-site reactions, eye symptoms, or elevated eosinophil levels.