Sneezing is a physiological reflex action that occurs when the nasal passages become irritated due to any cause. The act of sneezing is an effort to expel the irritant from the nasal passages. In most cases, sneezing is an acute event that happens in response to airborne pollutants, and lasts a few seconds to a few minutes. It may even last for a few days in case of an upper respiratory tract infection (such as common cold).
Sneezing may also be chronic, and may occur in the form of sneezing bouts or fits throughout the day. The sneezing bouts may continue intermittently over a period of many days meaning that it occurs on certain day but on other days there may be no swelling. This can persist for weeks, months or even years. Most of the cases of chronic sneezing are due to allergic reactions. Sneezing may even occur in people without allergies. In non-allergic individuals, exposure to smoke, dust and other irritants may cause chronic sneezing. However, sneezing is more pronounced in people with allergies.
Other Signs and Symptoms
Chronic sneezing is often accompanied by other head symptoms. Some of these other symptoms include:
- A runny nose is a common feature of an inflammatory nasal condition known as rhinitis, which is also characterized by sneezing.
- Itchy eyes and itchy nose may commonly occur along with chronic sneezing.
- Nasal passages may be congested, leading to labored breathing through the nose.
- Disruption of smelling capacity may also occur. This includes both hyposmia (lowering of smelling ability) and anosmia (total loss of smelling ability).
- The nostrils may appear red due to inflammation.
- Bloodshot eyes (reddish eyes) may be an accompanying feature.
- Excessively watery eyes are also a common occurrence alongside chronic sneezing.
In some rare cases, sneezing can occur on its own with no other symptoms indicative of nasal passage inflammation. This is more likely to be seen with neurologic (nerve-related) disorders that results in sneezing.
Causes of Persistent Sneezing
Most of the time chronic sneezing is related to inflammation of the nasal passages which is known as rhinitis. It is typically characterized by a runny and itchy nose, sneezing, and nasal congestion. There are many different types of rhinitis which arises for different reasons and due to a host of different causes. Broadly, based on its cause, rhinitis can be classified as either allergic and non-allergic.
An infection due to a virus, bacteria, and fungi is the most common non-allergic cause of rhinitis. Other non-allergic causes include certain drugs (such as those used for hypertension, erectile dysfunction, and anxiety), hormonal changes (especially in women), environmental irritants (such as smoke, smog, perfumes, and certain gases), foods (such as hot and spicy meals), and immune-mediated eosinophilic rhinitis.
Allergies are one the most common causes of chronic sneezing. Allergic rhinitis is a particularly widespread condition, which may occur throughout the year (perennial) or be seasonal (especially during spring). The most common trigger for allergic rhinitis are airborne allergens. However, food allergies are also common in individuals suffering from allergic rhinitis.
The most common airborne triggers for sneezing attacks in allergic rhinitis include pollen, grass, animal hair (dander), house mites, dust, fungal spores, strong odors (such as perfumes), and weather changes (especially cold and dry air). Some of the food allergens that may affect individuals with allergic rhinitis include dairy products, ice cold drinks, and spicy foods.
One of the most common features of allergic rhinitis is the occurrence of sneezing bouts after awakening from sleep in the morning (also known as morning sneezing fit).
Read more on allergic rhinitis.
Infections of the upper respiratory tract are also frequent causes of chronic sneezing. Since most of the upper respiratory tract infections are acute in nature, the accompanying bouts of sneezing are also short lived. However, sneezing may become chronic with persistent infection. This is most often the case with immunocompromised patients who are unable to fight infections.
The most common infections leading to infectious rhinitis are caused by viruses. Adenoviruses and rhinoviruses are usually the culprits. Chronic sneezing can also be caused by bacterial infections and inflammation of sinuses (sinusitis). Fungal infections can also causes chronic sneezing. However, fungal rhinitis happens rarely, and is mostly restricted to immunocompromised patients (for example, diabetics with mucormycosis).
Read more on influenza.
A variety of irritants can cause persistent and chronic sneezing. These triggers are classified under non-allergic and non-infectious causes, and could be airborne, ingested or systemic. The irritants include environmental pollution (such as smog), dust (both organic and inorganic), smoke (especially cigarette smoke), strong odors (such as deodorants, perfumes and spices), cold and dry weather conditions, hot and spicy foods, stress, and (in women) contraceptives and pregnancy.
Chronic sneezing caused by the use of certain medications is technically classified as drug-induced rhinitis. However, sneezing may also be caused in cases where the drugs cause excessive drying of the nasal passages without causing other rhinitis symptoms. Some of the drugs that can induce chronic sneezing include non-steroidal anti-inflammatory drugs (NSAIDs), beta-blockers (used for controlling hypertension), diuretics, sedatives, anti-depressants, oral contraceptives, drugs for erectile dysfunction, and nasal decongestants. Chronic sneezing caused by nasal decongestants is usually due to rebound rhinitis triggered by overuse of these medications.
Neurological conditions that may affect the trigeminal nerve (the largest cranial nerve) or the sneeze center in the medulla of the hindbrain can lead to chronic sneezing.
Nasal polyps are small, tear drop-shaped outgrowths that form in the nasal passages and sinuses. These are not cancerous, and are mostly a result of inflammation of the nasal mucosa. Nasal polyps are a chronic condition associated with allergic rhinitis and chronic sneezing.
Sniffing or snorting cocaine through the nose causes serious damage to the nasal passages. Chronic sneezing may be a feature of this addiction. Ground or pulverized tobacco leaves (called snuff) when stuffed into the nasal cavity, lead to sneezing. Chronic snuff use also leads to morphological and functional changes in the nasal mucosa. Professional swimmers who spend a lot of time in the chlorinated swimming pool waters are also susceptible to chronic sneezing as the chlorine irritates the nasal passages.