Allergic conjunctivitis
Encyclopedia
Allergic conjunctivitis
is inflammation
of the conjunctiva
(the membrane covering the white part of the eye) due to allergy
. Although allergen
s differ between patients, the most common cause is hay fever
. Symptoms consist of redness (mainly due to vasodilation
of the peripheral small blood vessels), oedema of the conjunctiva, itch
ing and increased lacrimation (production of tears
). If this is combined with rhinitis
, the condition is termed allergic rhinoconjunctivitis.
The symptoms are due to release of histamine
and other active substances by mast cell
s, which stimulate dilation of blood vessels, irritate nerve endings and increase secretion of tears.
Treatment of allergic conjunctivitis is by avoiding the allergen (e.g. avoiding grass in bloom during the "hay fever season") and treatment with antihistamine
s, either topical (in the form of eye drop
s), or systemic (in the form of tablets). Antihistamines, medication that stabilizes mast cells, and non-steroidal anti-inflammatory drugs (NSAIDs) are safe and usually effective.
is a thin membrane that covers the eye. When an allergen irritates the conjunctiva, common symptoms that occur in the eye include: ocular itching, eyelid swelling, tearing, photophobia, watery discharge, and foreign body sensation (with pain).
Itching is the most typical symptom of ocular allergy and more than 75% of patients report this symptom when seeking treatment.
Symptoms are usually worse for patients when the weather is warm and dry, whereas cooler temperatures and rain tend to assuage symptoms.
A study by Klein et al. showed that in addition to the physical discomfort allergic conjunctivitis causes, it also alters patients' routines, with patients limiting certain activities such as going outdoors, reading, sleeping, and driving. Therefore, treating patients with allergic conjunctivitis may improve their everyday "quality of life
."
Signs in PKC include small yellow nodules that develop over the cornea, which ulcerate after a few days.
. Allergic conjunctivitis is common in people who have other signs of allergic disease such as hay fever, asthma and eczema.
Among the most common allergens that cause conjunctivitis are:
Most cases of seasonal conjunctivitis are due to pollen
and occur in the hay fever season, grass pollens in early summer and various other pollens and moulds may cause symptoms later in the summer.
Perennial conjunctivitis is commonly due to an allergy to house dust mite (a tiny insect-like creature that lives in every home).
Giant papillary conjunctivitis is a very rare condition that is mainly caused by an allergic reaction to "debris
". Surgery may also cause this type of allergic conjunctivitis.
Contact dermatoconjunctivitis is caused by the rest of the allergens that conjunctiva may come into contact with: cosmetics, medications and so on.
s such as eotaxin
and MIP-1 alpha
have been implicated in the priming and activation of mast cells in the ocular surface. When a particular allergen is present, sensitization takes place and prepares the system to launch an antigen specific response. TH2 differentiated
T cell
s release cytokines, which promote the production of antigen specific immunoglobulin E
(IgE). IgE then binds to IgE receptors on the surface of mast cells. Then, mast cells release histamine
, which then leads to the release of cytokines, prostaglandin
s, and platelet-activating factor
. Mast cell intermediaries cause an allergic inflammation and symptoms through the activation of inflammatory cells.
When histamine
is released from mast cells, it binds to H1 receptors on nerve endings and causes the ocular symptom of itching. Histamine also binds to H1 and H2 receptors of the conjunctival vasculature and causes vasodilatation. Mast cell-derived cytokines such as chemokine interleukin IL-8
are involved in recruitment of neutrophils. TH2 cytokines such as IL-5
recruit eosinophils and IL-4
, IL-6
, and IL-13
, which promote increased sensitivity. Immediate symptoms are due to the molecular cascade. Encountering the allergen a patient is sensitive to leads to increased sensitation of the system and more powerful reactions. Advanced cases can progress to a state of chronic allergic inflammation.
, mast cell stabilizer
s, dual mechanism anti-allergen agents, or topical antihistamines. Corticosteroid
s are another option, but, considering the side-effects of cataracts and increased intraocular pressure
, corticosteroids are reserved for more severe forms of allergic conjunctivitis such as vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC).
and atopic keratoconjunctivitis are chronic allergic diseases wherein eosinophils, conjunctival fibroblasts, epithelial cells, mast cells, and TH2 lymphocytes aggravate the biochemistry and histology of the conjunctiva
. VKC is a disease of childhood and is prevalent in males living in warm climates. AKC is frequently observed in males between the ages of 30 and 50. VKC and AKC can be treated by medications used to combat allergic conjunctivitis or the use of steroids.
Common pathogens include Staph. aureus, Mycobacterium tuberculosis
, Chlamydia
and Candida
.
If the allergen is encountered and the symptoms are mild, a cold compress can be used to provide relief. It is a quick and easy solution without using any medications. The cold temperature of the water will help to bring down swelling, as it would in a bruise or burn. In addition, there are many antihistamine medications available for purchase.
Mast cell
stabilizers can help curing patients with allergic conjunctivitis when cold compress are no longer effective. They tend to have delayed results, but they have fewer side-effects than the other treatments and last much longer than those of antihistamines. Some patients are given an antihistamine at the same time so that there is some relief of symptoms before the mast cell stabilizers becomes effective. Doctors commonly prescribe lodoxamide
and nedocromil
as mast cell stabilizers, which come as eye drops.
A mast cell stabilizer is a class of non-steroid controller medicine that reduces the release of inflammation-causing chemicals from mast cells. They block a calcium channel essential for mast cell degranulation, stabilizing the cell, thus preventing the release of histamine
. Decongestants may also be prescribed. Another common mast cell stabilizer that is used for treating allergic conjunctivitis is sodium cromoglicate.
Antihistamine medications are frequently prescribed because they provide immediate relief from the itch and burning symptoms.
Dual-action medications are also prescribed frequently. Olopatadine (Patanol) and Ketotifen Fumarate (Alaway or Zaditor) both provide protection by acting as an antihistamine and a mast cell stabilizer together. Patanol is a prescription medication, whereas Ketotifen Fumarate is not.
It is mandatory that the patients not use anything besides clean, warm water until visiting their doctors. Many of the eye drops can cause burning and stinging, and usually nearly all medications have side-effects. Therefore, patients are strongly recommended to first talk to their doctors before using any type of medication.
Individuals prone to developing allergenic conjunctivitis may prevent getting the condition by having proper eye hygiene
, especially if wearing contact lenses. People allergic to pollen or mold are also advised to stay indoors when allergen levels are high. Allergic persons are recommended to keep the doors and windows closed and use air conditioners during the summer months to prevent developing allergic conjunctivitis.
Allergic conjunctivitis is a frequent condition as it is estimated to affect 20 percent of the population
on an annual basis and approximately one-half of these people have a personal or family history of atopy
.
Giant papillary conjunctivitis accounts for 0.5–1.0% of eye disease in most countries.
Conjunctivitis
Conjunctivitis refers to inflammation of the conjunctiva...
is inflammation
Allergic inflammation
Allergic inflammation is an important pathophysiological feature of several disabilities or medical conditions including allergic asthma, atopic dermatitis, allergic rhinitis and several ocular allergic diseases. Allergic reactions may generally be divided into two components; the early phase...
of the conjunctiva
Conjunctiva
The conjunctiva covers the sclera and lines the inside of the eyelids. It is composed of rare stratified columnar epithelium.-Function:...
(the membrane covering the white part of the eye) due to allergy
Allergy
An Allergy is a hypersensitivity disorder of the immune system. Allergic reactions occur when a person's immune system reacts to normally harmless substances in the environment. A substance that causes a reaction is called an allergen. These reactions are acquired, predictable, and rapid...
. Although allergen
Allergen
An allergen is any substance that can cause an allergy. In technical terms, an allergen is a non-parasitic antigen capable of stimulating a type-I hypersensitivity reaction in atopic individuals....
s differ between patients, the most common cause is hay fever
Hay Fever
Hay Fever is a comic play written by Noël Coward in 1924 and first produced in 1925 with Marie Tempest as the first Judith Bliss. Laura Hope Crews played the role in New York...
. Symptoms consist of redness (mainly due to vasodilation
Vasodilation
Vasodilation refers to the widening of blood vessels resulting from relaxation of smooth muscle cells within the vessel walls, particularly in the large arteries, smaller arterioles and large veins. The process is essentially the opposite of vasoconstriction, or the narrowing of blood vessels. When...
of the peripheral small blood vessels), oedema of the conjunctiva, itch
Itch
Itch is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to classify it as any one type of sensory experience. Modern science has shown that itch has many similarities to pain, and while both are unpleasant sensory experiences, their behavioral response...
ing and increased lacrimation (production of tears
Tears
Tears are secretions that clean and lubricate the eyes. Lacrimation or lachrymation is the production or shedding of tears....
). If this is combined with rhinitis
Rhinitis
Rhinitis , commonly known as a stuffy nose, is the medical term describing irritation and inflammation of some internal areas of the nose. The primary symptom of rhinitis is nasal dripping. It is caused by chronic or acute inflammation of the mucous membrane of the nose due to viruses, bacteria or...
, the condition is termed allergic rhinoconjunctivitis.
The symptoms are due to release of histamine
Histamine
Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by...
and other active substances by mast cell
Mast cell
A mast cell is a resident cell of several types of tissues and contains many granules rich in histamine and heparin...
s, which stimulate dilation of blood vessels, irritate nerve endings and increase secretion of tears.
Treatment of allergic conjunctivitis is by avoiding the allergen (e.g. avoiding grass in bloom during the "hay fever season") and treatment with antihistamine
Antihistamine
An H1 antagonist is a histamine antagonist of the H1 receptor that serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions...
s, either topical (in the form of eye drop
Eye drop
Eye drops are saline-containing drops used as a route to administer medication in the eye. Depending on the condition being treated, they may contain steroids, antihistamines, sympathomimetics, beta receptor blockers, parasympathomimetics, parasympatholytics, prostaglandins, non-steroidal...
s), or systemic (in the form of tablets). Antihistamines, medication that stabilizes mast cells, and non-steroidal anti-inflammatory drugs (NSAIDs) are safe and usually effective.
Signs and symptoms
The conjunctivaConjunctiva
The conjunctiva covers the sclera and lines the inside of the eyelids. It is composed of rare stratified columnar epithelium.-Function:...
is a thin membrane that covers the eye. When an allergen irritates the conjunctiva, common symptoms that occur in the eye include: ocular itching, eyelid swelling, tearing, photophobia, watery discharge, and foreign body sensation (with pain).
Itching is the most typical symptom of ocular allergy and more than 75% of patients report this symptom when seeking treatment.
Symptoms are usually worse for patients when the weather is warm and dry, whereas cooler temperatures and rain tend to assuage symptoms.
A study by Klein et al. showed that in addition to the physical discomfort allergic conjunctivitis causes, it also alters patients' routines, with patients limiting certain activities such as going outdoors, reading, sleeping, and driving. Therefore, treating patients with allergic conjunctivitis may improve their everyday "quality of life
Quality of life
The term quality of life is used to evaluate the general well-being of individuals and societies. The term is used in a wide range of contexts, including the fields of international development, healthcare, and politics. Quality of life should not be confused with the concept of standard of...
."
Signs in PKC include small yellow nodules that develop over the cornea, which ulcerate after a few days.
Causes
The cause of allergic conjunctivitis is an allergic reaction of the body's immune system to an allergenAllergen
An allergen is any substance that can cause an allergy. In technical terms, an allergen is a non-parasitic antigen capable of stimulating a type-I hypersensitivity reaction in atopic individuals....
. Allergic conjunctivitis is common in people who have other signs of allergic disease such as hay fever, asthma and eczema.
Among the most common allergens that cause conjunctivitis are:
- PollenPollenPollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
from trees, grass and ragweed - Animal skin and secretions such as salivaSalivaSaliva , referred to in various contexts as spit, spittle, drivel, drool, or slobber, is the watery substance produced in the mouths of humans and most other animals. Saliva is a component of oral fluid. In mammals, saliva is produced in and secreted from the three pairs of major salivary glands,...
- Perfumes
- CosmeticsCosmeticsCosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...
- Skin medicines
- Air pollutionAir pollutionAir pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or cause damage to the natural environment or built environment, into the atmosphere....
- SmokeSmokeSmoke is a collection of airborne solid and liquid particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires , but may also be used for pest...
- Dust mites
- Eye drops
Most cases of seasonal conjunctivitis are due to pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
and occur in the hay fever season, grass pollens in early summer and various other pollens and moulds may cause symptoms later in the summer.
Perennial conjunctivitis is commonly due to an allergy to house dust mite (a tiny insect-like creature that lives in every home).
Giant papillary conjunctivitis is a very rare condition that is mainly caused by an allergic reaction to "debris
Debris
Debris is rubble, wreckage, ruins, litter and discarded garbage/refuse/trash, scattered remains of something destroyed, or, in geology, large rock fragments left by a melting glacier etc. The singular form of debris is debris...
". Surgery may also cause this type of allergic conjunctivitis.
Contact dermatoconjunctivitis is caused by the rest of the allergens that conjunctiva may come into contact with: cosmetics, medications and so on.
Pathophysiology
The ocular allergic response is a cascade of events that is coordinated by mast cells. Beta chemokineChemokine
Chemokines are a family of small cytokines, or proteins secreted by cells. Their name is derived from their ability to induce directed chemotaxis in nearby responsive cells; they are chemotactic cytokines...
s such as eotaxin
Eotaxin
Eotaxin may refer to:* CCL11 * CCL24 * CCL26...
and MIP-1 alpha
CCL3
Chemokine ligand 3 is a protein that in humans is encoded by the CCL3 gene.-Further reading:...
have been implicated in the priming and activation of mast cells in the ocular surface. When a particular allergen is present, sensitization takes place and prepares the system to launch an antigen specific response. TH2 differentiated
T helper cell
T helper cells are a sub-group of lymphocytes, a type of white blood cell, that play an important role in the immune system, particularly in the adaptive immune system. These cells have no cytotoxic or phagocytic activity; they cannot kill infected host cells or pathogens. Rather, they help other...
T cell
T cell
T cells or T lymphocytes belong to a group of white blood cells known as lymphocytes, and play a central role in cell-mediated immunity. They can be distinguished from other lymphocytes, such as B cells and natural killer cells , by the presence of a T cell receptor on the cell surface. They are...
s release cytokines, which promote the production of antigen specific immunoglobulin E
Immunoglobulin E
Immunoglobulin E is a class of antibody that has been found only in mammals. IgE is a monomeric antibody with 4 Ig-like domains...
(IgE). IgE then binds to IgE receptors on the surface of mast cells. Then, mast cells release histamine
Histamine
Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by...
, which then leads to the release of cytokines, prostaglandin
Prostaglandin
A prostaglandin is any member of a group of lipid compounds that are derived enzymatically from fatty acids and have important functions in the animal body. Every prostaglandin contains 20 carbon atoms, including a 5-carbon ring....
s, and platelet-activating factor
Platelet-activating factor
Platelet-activating factor, also known as a PAF, PAF-acether or AGEPC is a potent phospholipid activator and mediator of many leukocyte functions, including platelet aggregation and degranulation, inflammation, and anaphylaxis...
. Mast cell intermediaries cause an allergic inflammation and symptoms through the activation of inflammatory cells.
When histamine
Histamine
Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by...
is released from mast cells, it binds to H1 receptors on nerve endings and causes the ocular symptom of itching. Histamine also binds to H1 and H2 receptors of the conjunctival vasculature and causes vasodilatation. Mast cell-derived cytokines such as chemokine interleukin IL-8
IL-8
IL-8 can refer to:* Interleukin 8, a chemokine of the immune system* Illinois' 8th congressional district* Illinois Route 8...
are involved in recruitment of neutrophils. TH2 cytokines such as IL-5
Interleukin 5
Interleukin 5 or IL-5 is an interleukin produced by T helper-2 cells and mast cells. Its functions are to stimulate B cell growth and increase immunoglobulin secretion. It is also a key mediator in eosinophil activation. IL-5 is a 115-amino acid -long TH2 cytokine that is part of the...
recruit eosinophils and IL-4
Interleukin 4
Interleukin-4, abbreviated IL-4, is a cytokine that induces differentiation of naive helper T cells to Th2 cells. Upon activation by IL-4, Th2 cells subsequently produce additional IL-4. The cell that initially produces IL-4, thus inducing Th0 differentiation, has not been identified, but recent...
, IL-6
Interleukin 6
Interleukin-6 is a protein that in humans is encoded by the IL6 gene.IL-6 is an interleukin that acts as both a pro-inflammatory and anti-inflammatory cytokine. It is secreted by T cells and macrophages to stimulate immune response, e.g. during infection and after trauma, especially burns or other...
, and IL-13
Interleukin 13
Interleukin 13 is a protein that in humans is encoded by the IL13 gene. IL-13 is cytokine secreted by many cell types, but especially T helper type 2 cells, that is a mediator of allergic inflammation and disease.-Functions:...
, which promote increased sensitivity. Immediate symptoms are due to the molecular cascade. Encountering the allergen a patient is sensitive to leads to increased sensitation of the system and more powerful reactions. Advanced cases can progress to a state of chronic allergic inflammation.
SAC and PAC
Both seasonal allergic conjunctivitis and perennial allergic conjunctivitis are two acute allergic conjunctival disorders. SAC is the most common ocular allergy. Symptoms of the aforementioned ocular diseases include itching and pink to reddish eye(s). These two eye conditions are mediated by mast cells. Nonspecific measures to ameliorate symptoms include cold compresses, eyewashes with tear substitutes, and avoidance of allergens. Treatment consists of antihistamineAntihistamine
An H1 antagonist is a histamine antagonist of the H1 receptor that serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions...
, mast cell stabilizer
Mast cell stabilizer
Mast cell stabilizers are cromone medications used to prevent or control certain allergic disorders. They block a calcium channel essential for mast cell degranulation, stabilizing the cell and thereby preventing the release of histamine and related mediators. One suspected pharmacodynamic...
s, dual mechanism anti-allergen agents, or topical antihistamines. Corticosteroid
Corticosteroid
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. Corticosteroids are involved in a wide range of physiologic systems such as stress response, immune response and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte...
s are another option, but, considering the side-effects of cataracts and increased intraocular pressure
Intraocular pressure
Intraocular pressure is the fluid pressure inside the eye. Tonometry is the method eye care professionals use to determine this. IOP is an important aspect in the evaluation of patients at risk from glaucoma...
, corticosteroids are reserved for more severe forms of allergic conjunctivitis such as vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC).
VKC and AKC
Both vernal keratoconjunctivitisVernal keratoconjunctivitis
Vernal keratoconjunctivitis or Spring catarrh is a recurrent, bilateral, and self limiting inflammation of conjunctiva, having a periodic seasonal incidence.-Etiology:...
and atopic keratoconjunctivitis are chronic allergic diseases wherein eosinophils, conjunctival fibroblasts, epithelial cells, mast cells, and TH2 lymphocytes aggravate the biochemistry and histology of the conjunctiva
Conjunctiva
The conjunctiva covers the sclera and lines the inside of the eyelids. It is composed of rare stratified columnar epithelium.-Function:...
. VKC is a disease of childhood and is prevalent in males living in warm climates. AKC is frequently observed in males between the ages of 30 and 50. VKC and AKC can be treated by medications used to combat allergic conjunctivitis or the use of steroids.
Giant papillary conjunctivitis
Giant papillary conjunctivitis is not a true ocular allergic reaction and is caused by repeated mechanical irritation of the conjunctiva. Repeated contact with the conjunctival surface caused by the use of contact lenses is associated with GPC.Phlyctenular keratoconjunctivitis
PKC results from a hypersensitivity/inflammatory reaction to bacteria.Common pathogens include Staph. aureus, Mycobacterium tuberculosis
Mycobacterium tuberculosis
Mycobacterium tuberculosis is a pathogenic bacterial species in the genus Mycobacterium and the causative agent of most cases of tuberculosis . First discovered in 1882 by Robert Koch, M...
, Chlamydia
Chlamydia (bacterium)
Chlamydia is a genus of bacteria that are obligate intracellular parasites. Chlamydia infections are the most common bacterial sexually transmitted infections in humans and are the leading cause of infectious blindness worldwide....
and Candida
Candida (genus)
Candida is a genus of yeasts. Many species are harmless commensals or endosymbionts of animal hosts including humans, but other species, or harmless species in the wrong location, can cause disease. Candida albicans can cause infections in humans and other animals, especially in immunocompromised...
.
Treatment
A detailed history allows physicians to determine whether the presenting symptoms are due to an allergen or another source. Diagnostic tests such as conjunctival scrapings to look for eosinophils are helpful in determining the cause of the allergic response. Antihistamines, medication that stabilizes mast cells, and non-steroidal anti-inflammatory drugs (NSAIDs) are safe and usually effective. Corticosteroids are reserved for more severe cases of ocular allergy disease, and their use should be monitored by an eye care physician due to possible side-effects. When an allergen is identified, the patient should avoid the allergen as much as possible.If the allergen is encountered and the symptoms are mild, a cold compress can be used to provide relief. It is a quick and easy solution without using any medications. The cold temperature of the water will help to bring down swelling, as it would in a bruise or burn. In addition, there are many antihistamine medications available for purchase.
Mast cell
Mast cell
A mast cell is a resident cell of several types of tissues and contains many granules rich in histamine and heparin...
stabilizers can help curing patients with allergic conjunctivitis when cold compress are no longer effective. They tend to have delayed results, but they have fewer side-effects than the other treatments and last much longer than those of antihistamines. Some patients are given an antihistamine at the same time so that there is some relief of symptoms before the mast cell stabilizers becomes effective. Doctors commonly prescribe lodoxamide
Lodoxamide
Lodoxamide is an antiallergic. It resembles sodium cromoglycate in action as a mast cell stabilizer....
and nedocromil
Nedocromil
Nedocromil sodium is a medication used to prevent wheezing, shortness of breath, and other breathing problems caused by asthma. It is administered by an inhaler under the brand name Tilade and as an eye drop under the brand name Alocril...
as mast cell stabilizers, which come as eye drops.
A mast cell stabilizer is a class of non-steroid controller medicine that reduces the release of inflammation-causing chemicals from mast cells. They block a calcium channel essential for mast cell degranulation, stabilizing the cell, thus preventing the release of histamine
Histamine
Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by...
. Decongestants may also be prescribed. Another common mast cell stabilizer that is used for treating allergic conjunctivitis is sodium cromoglicate.
Antihistamine medications are frequently prescribed because they provide immediate relief from the itch and burning symptoms.
Dual-action medications are also prescribed frequently. Olopatadine (Patanol) and Ketotifen Fumarate (Alaway or Zaditor) both provide protection by acting as an antihistamine and a mast cell stabilizer together. Patanol is a prescription medication, whereas Ketotifen Fumarate is not.
It is mandatory that the patients not use anything besides clean, warm water until visiting their doctors. Many of the eye drops can cause burning and stinging, and usually nearly all medications have side-effects. Therefore, patients are strongly recommended to first talk to their doctors before using any type of medication.
Individuals prone to developing allergenic conjunctivitis may prevent getting the condition by having proper eye hygiene
Hygiene
Hygiene refers to the set of practices perceived by a community to be associated with the preservation of health and healthy living. While in modern medical sciences there is a set of standards of hygiene recommended for different situations, what is considered hygienic or not can vary between...
, especially if wearing contact lenses. People allergic to pollen or mold are also advised to stay indoors when allergen levels are high. Allergic persons are recommended to keep the doors and windows closed and use air conditioners during the summer months to prevent developing allergic conjunctivitis.
Epidemiology
Allergic conjunctivitis occurs more frequently among those with allergic conditions, with the symptoms having a seasonal correlation.Allergic conjunctivitis is a frequent condition as it is estimated to affect 20 percent of the population
Population
A population is all the organisms that both belong to the same group or species and live in the same geographical area. The area that is used to define a sexual population is such that inter-breeding is possible between any pair within the area and more probable than cross-breeding with individuals...
on an annual basis and approximately one-half of these people have a personal or family history of atopy
Atopy
Atopy or atopic syndrome is a predisposition toward developing certain allergic hypersensitivity reactions.Atopy may have a hereditary component, although contact with the allergen must occur before the hypersensitivity reaction can develop ....
.
Giant papillary conjunctivitis accounts for 0.5–1.0% of eye disease in most countries.