is a medical term for irritation and inflammation of the mucous membrane
inside the nose. Common symptoms of rhinitis are a stuffy nose,
runny nose,
and post-nasal drip.
The most common kind of rhinitis is allergic rhinitis,
which is usually triggered by airborne allergens
such as pollen
and dander.
Allergic rhinitis may cause additional symptoms, such as sneezing and nasal
itching, coughing, headache, fatigue, malaise, and cognitive impairment.
The allergens may also affect the eyes, causing watery, reddened or itchy eyes
and puffiness around the eyes.
Rhinitis is very common. Allergic rhinitis is more common in some countries than others; in the United
States, about 10%-30% of adults are affected annually.
In rhinitis, the inflammation
of the mucous membrane is caused by viruses, bacteria,
irritants or allergens. The inflammation results in the generation of large
amounts of mucus,
commonly producing a runny nose, as well as a stuffy nose
and post-nasal drip. In the case of allergic rhinitis, the inflammation is caused by the degranulation of mast cells
in the nose. When mast cells degranulate, they release histamine
and other chemicals,
starting an inflammatory process that can cause symptoms outside the nose, such
as fatigue and malaise.
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Contents
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Types
Rhinitis is categorized into three
types: (i) infective rhinitis includes acute and chronic bacterial infections;
(ii) nonallergic (vasomotor)
rhinitis includes autonomic, hormonal,
drug-induced, atrophic, and gustatory rhinitis, as well as rhinitis medicamentosa; (iii) allergic rhinitis, triggered by pollen, mold, animal dander, dust and other similar inhaled
allergens
Infectious
Rhinitis is commonly caused by a
viral or bacterial infection, including the common cold, which is caused by Rhinoviruses
and Coronaviruses, or bacterial sinusitis.
Symptoms of the common cold include rhinorrhea,
sore throat (pharyngitis), cough, congestion,
and slight headache
Vasomotor rhinitis
Non-allergic rhinitis refers to
runny nose that is not due to allergy. Non-allergic rhinitis can be classified
as either non-inflammatory or inflammatory rhinitis. One very common type of
non-inflammatory, non-allergic rhinitis that is sometimes confused with allergy
is called vasomotor rhinitis, in which certain non-allergic triggers
such as smells, fumes, smoke, dusts, and temperature changes, cause rhinitis.
There is still much to be learned about this entity, but it is thought that
these non-allergic triggers cause dilation of the blood vessels in the lining
of the nose, which results in swelling, and drainage. Vasomotor rhinitis can
coexist with allergic rhinitis, and this is called "mixed rhinitis."
(Middleton's Allergy Principles and Practice, seventh edition.) The pathology
of vasomotor rhinitis appears to involve neurogenic inflammation
and is as yet not very well understood. Vasomotor rhinitis appears to be
significantly more common in women than men, leading some researchers to
believe that hormones play a role. In general, age of onset occurs after 20
years of age, in contrast to allergic rhinitis which can be developed at any
age. Individuals suffering from vasomotor rhinitis typically experience
symptoms year-round, though symptoms may be exacerbated in the spring and
autumn when rapid weather changes are more common.
An estimated 17 million United States
citizens have vasomotor rhinitis. The antihistamines azelastine and
olopatadine, applied as nasal sprays, may both be effective for vasomotor
rhinitis.
Fluticasone propionate or budesonide (both are steroids)
in nostril spray form may also be used for symptomatic treatment.
Allergic
Main article: Allergic rhinitis
Pollen
grains from a variety of common plants can cause hay fever.
Allergic rhinitis or hay fever is
when an allergen such as pollen or dust is inhaled by an individual with a
sensitized immune system, triggering antibody
production. These antibodies mostly bind to mast cells,
which contain histamine. When the mast cells are stimulated by pollen and dust,
histamine (and other chemicals) are released. This causes itching, swelling,
and mucus
production. Symptoms vary in severity between individuals. Very sensitive
individuals can experience hives or other rashes. Particulate matter in polluted air and chemicals such as chlorine
and detergents, which can normally be tolerated, can greatly aggravate the
condition.[citation needed]
Characteristic physical findings in
individuals who have allergic rhinitis include conjunctival swelling and
erythema, eyelid swelling, lower eyelid venous stasis, lateral crease on the
nose, swollen nasal turbinates, and middle ear effusion
Even if a person has negative skin-prick, intradermal and blood tests for allergies, they may still have allergic rhinitis, from
a local allergy in the nose. This is called local allergic rhinitis.
Many people who were previously diagnosed with nonallergic rhinitis may
actually have local allergic rhinitis.
Rhinitis
medicamentosa
Main article: Rhinitis medicamentosa
It is a condition of rebound
nasal congestion brought on by extended use of topical decongestants (e.g., oxymetazoline,
phenylephrine, xylometazoline,
and naphazoline nasal sprays) that work by constricting blood vessels in the lining of
the nose.
Chronic
atrophic rhinitis
Main article: Chronic
atrophic rhinitis
Rhinitis
sicca
Chronic form of dryness of the
mucous membranes
Polypous
rhinitis
Management
The management of rhinitis depends
on the underlying cause. High-dose administration of Vitamin B12
has been additionally validated to stimulate the activity of the body's TH1
suppressor T-Cells, which then down-regulates the over-production of the
allergen antibody IgE in allergic individuals which could decrease both near
and long term manifestations of rhinitis symptomology.
