Linda Crampton is an experienced teacher with a first-class honors degree in biology. She writes about the scientific basis of disease.
The Conjunctiva and Conjunctivitis
The conjunctiva is a thin mucous membrane that covers the white part of the eye and lines the inside of the eyelid. The membrane is usually clear and colorless, but if it's irritated or infected it may become inflamed. Possible symptoms of this inflammation include red and itchy eyes, swollen eyelids, and a discharge. The inflammation is known as conjunctivitis or pink eye. It's a condition that I occasionally experience myself.
Our eyes produce several types of tears. One type is released regularly to form a protective film over the surface of the eye. These tears wash particles away from the eye's surface and also contain chemicals that fight infection. This helps to prevent conjunctivitis. Unfortunately, older people—especially women—often produce fewer of these beneficial tears than younger ones and have an increased chance of developing conjunctivitis. Low tear production can result in chronically dry eyes, a condition known as dry eye syndrome or keratoconjunctivitis sicca.
Seek Help When Necessary
The information in this article is presented for general interest. Make sure that you contact a doctor if you have an eye problem that worries you or questions about your health or the health of someone that you care for.
An Ophthamologist Discusses Pink Eye
Four Types of Conjunctivitis
Several types of conjunctivitis exist. Infective conjunctivitis is caused by a bacterium or a virus; allergic conjunctivitis results when the eye is exposed to an allergen; and irritant conjunctivitis is produced by contact with irritating chemicals. Wearing contact lenses for a long time may also irritate the eyes and cause conjunctivitis.
The most common cause of infectious conjunctivitis is a virus. Viruses that cause the common cold and the flu can both cause the condition. In most cases, there is no medical cure for the infection, so the body has to deal with the problem by itself. Antiviral drugs are available to fight a few of the viruses that cause conjunctivitis, however. A doctor should be consulted for a diagnosis and for information about the possibility of drug treatment.
It may take a week to ten days before the redness and itching of viral conjunctivitis disappear. During this time, it's easy to pass the infection to someone else or to pass it from one eye to the other. Steps to prevent this process are important. I've given some tips for preventing the spread of the infection below.
Bacterial conjunctivitis produces similar symptoms to viral conjunctivitis, except there may be a thick, yellow, and sticky discharge released from the eyes instead of the watery discharge present in viral conjunctivitis. The bacteria that infect the conjunctiva may come from the person's own skin or respiratory tract, or they may be transferred from another person who has conjunctivitis. It's possible to have both viral and bacterial conjunctivitis at the same time. Bacterial conjunctivitis can often be treated with antibiotic eye drops.
Conjunctivitis can be caused by allergic reactions to materials such as pollen grains, dust mites, and pet dander (skin cells that are shed by the pet).
Examples of substances that can trigger irritant conjunctivitis include cigarette smoke, pollutants, chlorine in swimming pools, some fragrances, soap, hairspray, cleaning liquids, and diesel exhaust.
Some Possible Symptoms of Conjunctivitis
People suffering from conjunctivitis may experience one or more of the following symptoms.
- itchy or painful eyes
- a red and bloodshot sclera (the "white" of the eye) and red inner eyelids
- increased tear production
- an eye discharge
- blurred vision
- swollen eyelids
- sensitivity to light
- a gritty sensation in the eyes
- the formation of a crust on the inside of the eyelid while the person sleeps
- sticky eyelids
- difficulty in opening the eyes
Dealing With Pink Eye
So far, whenever I've had pink eye, the problem has cleared up on its own within a few days. The CDC says that it isn't always necessary to seek a doctor's advice when experiencing conjunctivitis. It lists some situations in which a medical consultation is important, however. People should pay attention to the organization's recommendations. It says that a doctor should be visited if a person is experiencing moderate or severe pain, intense redness, or vision problems. A condition that fails to clear up on its own or with self-treatment also requires medical attention.
Possible Treatments for the Disorder
Conjunctivitis is annoying, uncomfortable, and embarrassing, but it's generally not serious. There are exceptions to this rule, though. One exception is conjunctivitis that is caused by sexually transmitted bacteria. These may infect other parts of the body besides the primary infection site and can cause serious eye damage, including blindness.
The treatment of conjunctivitis depends on its cause and on a doctor's advice.
- Artificial tear solutions may help to relieve the discomfort of viral conjunctivitis. These solutions are sometimes called lubricating eye drops. Some solutions contain preservatives while others don't. More information about the drops is provided below.
- Antibiotic eye drops, ointment, or pills may be prescribed for bacterial conjunctivitis.
- Antihistamine drops and pills may help allergic conjunctivitis.
- In severe cases of allergic conjunctivitis, a doctor may prescribe corticosteroid drops.
- Avoiding further exposure to allergens or irritants should help allergic or irritant conjunctivitis to disappear.
- Cool compresses applied several times a day may soothe the eyes and reduce redness and swelling in any type of conjunctivitis. (Use a clean washcloth to make each compress.)
Decongestant eye drops, also known as whitening drops, are available in stores. These drops reduce the bloodshot appearance of eyes by shrinking the blood vessels in the cornea. If they're used too often, however, they may cause rebound hyperemia. This is a condition in which the redness in the eyes is increased instead of decreased.
Tips for Preventing Pink Eye
In order to prevent conjunctivitis, it's important to keep the eyes clean. This is especially true for older adults, who don't get as much help from tears as younger people. Here are some tips that will reduce the chance that you will develop conjunctivitis.
- Keep your hands away from your eyes as much as possible.
- Wash your hands regularly. It's easy to rub an eye without thinking about it.
- Make sure that anything that comes close to your eyes, such as cosmetics, towels, and washcloths, is clean.
- Don't share towels or washcloths with other people.
- Buy fresh cosmetics regularly and discard the old ones.
- Handle and clean extended wear contact lenses properly.
- Wash pillow cases frequently.
- If you use a tissue on your face or to wipe your nose, discard it immediately and safely after use so that it doesn't infect your eyes or those of other people. In addition, wash your hands.
- If you have chronic dry eyes, visit a doctor to determine the cause. If you are advised to do so, use a treatment that increases the presence of tears.
A problem with tear production increases the risk of conjunctivitis. As we age, we produce fewer beneficial tears and the chance of developing conjunctivitis increases.
Types and Functions of Tears
Tears and tear production are important factors in dry eyes and conjunctivitis, especially in older people. Though someone with dry eyes may not have conjunctivitis, the risk of the second condition is increased.
Three types of tears exist. They differ slightly in composition. Basal tears lubricate the eye. Irritant or reflex tears are made in response to irritants in the eyes, as their name suggests. The third type of tear is the emotional or psychic tear.
Basal tears are the most important type with respect to dry eyes. They are a mixture of three types of fluid—an outer oily layer, a middle watery layer, and an inner mucus layer—which are made by glands around the eye.
- The oil component is made by glands at the edge of the upper and lower eyelids called meibomian glands. The oil stops the tears from evaporating once they are spread over the eye.
- The lacrimal gland produces the watery component of the tears, which forms the majority of the tear. This watery material contains proteins. The lacrimal gland is located above each eye, towards its outer edge, and sends its secretion to the eye via ducts.
- Goblet cells in the conjunctiva produce mucin, which forms mucus when mixed with water. The mucus layer helps the tears stick to the eye.
Every time we blink, tears flow over the surface of the eyes. The tear film lubricates the eyes, keeps them moist, and cleans them. Tears are necessary in order for us to have clear vision. They also contain antibodies and enzymes that destroy bacteria and viruses. Once they have covered the front of the eyes, any left over tears enter drainage ducts in the inner corner of each eye. These ducts transport the fluid to the back of our nose.
Tear Production in Older Adults
Tear production decreases as we age. According to the American Optometric Association, the majority of people over the age of 65 have some dry eye symptoms. Dry eyes are more common in women than in men, especially after menopause. Hormonal changes are believed to be at least partly responsible for the decreased tear production. There are other possible reasons for the problem besides age, however, so if you're an older person with dry eyes don't assume that your problem is due to your age.
Keratoconjunctivitis sicca or dry eye syndrome can make blinking painful and cause the eyes to feel gritty. The eyes may also be red and irritated. There may actually be an increase in tear production, but these are irritant tears and aren't helpful for lubrication. Prolonged or severe dry eye syndrome can damage the cornea on the surface of the eye, which is normally protected by a tear film.
Other Causes of Dry Eyes Besides Aging
Some factors that may cause dry eye syndrome in addition to age are certain medical conditions (such as rheumatoid arthritis, lupus, diabetes, and Sjogren's syndrome) and certain medications (including antihistamines, decongestants, diuretics, and some drugs that are prescribed to treat high blood pressure).
Eyelid problems may reduce the blinking rate, thereby reducing the flow of tears over the eye. A vitamin A deficiency may also cause dry eyes. There is some evidence that a diet low in omega-3 fatty acids may predispose a person to developing the condition.
Being in a windy environment or in one with dry air can cause temporarily dry eyes. Other activities that may produce the effect include ones that reduce blinking, such as driving, reading, studying, and working at a computer for a long time. Certain types of laser eye surgery may reduce tear production temporarily.
Blepharitis is an inflammation of the eyelids near the lashes and may be accompanied by dry eyes. Blepharitis is often (but not always) caused by an infection. The inflammation can interfere with the action of the oil-producing meibomian glands, which are located along the edge of the eyelids. Sometimes a problem with these glands is the cause of blepharitis rather than the result. In either case, since the oil from the meibomian glands reduces the evaporation of the tear film, without its presence dry eyes may result. This increases the chance of conjunctivitis development.
The Use of Artificial Tears for Dry Eyes
If you are suffering from chronically dry eyes or experience the condition frequently, it's important to visit a doctor to find an explanation. The problem may be easily solved. It may be due to another illness that must be treated, however.
If the doctor finds that there is no obvious cause for the condition, such as a medical problem or the use of a particular medication, artificial tears may be a useful aid. They can often relieve discomfort, improve vision, and help to improve the condition of the surface of the eye.
Preservative-free artificial tears frequently come in single-use containers, so using them regularly may become expensive. They can be helpful if a preservative irritates the eyes, however. Artificial tears with a preservative are less expensive, and a bottle generally lasts for a longer time. As long as the preservative doesn't cause irritation, they might be a good product to use. A product's instructions regarding the frequency of application should be read carefully. A doctor or a pharmacist should be able to recommend a suitable version of artificial tears.
Possible Medical Treatments for Dry Eyes
Doctors can offer a wide variety of treatments to help dry eyes. They can prescribe other types of drops and medications to help patients in addition to common drug store products.
In a serious case of dry eyes that doesn't respond to conservative treatment, a surgeon may block the drainage ducts that remove tears. This should cause the tears to stay in the eyes for a longer time period. The blocked drainage ducts can be opened at a later date if necessary.
It's worth finding a good solution to a dry eye problem in order to reduce discomfort and the possibility of cornea damage. Like conjunctivitis, dry eyes may be an uncomfortable but temporary problem. A disorder that is painful, becomes chronic, or occurs repeatedly needs to be investigated by a doctor in order to find relief for the problem and protect vision.
- Conjunctivitis information from the Centers for Disease Control and Prevention (CDC)
- Pink eye facts from WebMD
- Information about dry eyes from the American Optometric Association (AOA)
- Blepharitis facts from the Mayo Clinic
- Eye problems that become more likely as we age from WebMD
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
© 2012 Linda Crampton
Linda Crampton (author) from British Columbia, Canada on September 13, 2012:
Hi, teaches. I experience allergic pink eye at times - it's not very pleasant! Thanks for the comment and the vote.
Dianna Mendez on September 13, 2012:
I remember getting pink eye a few times as a child and a couple of times as an adult. It is a bit annoying and embarrassing if you have to be around people. Good hub information on how to keep it from spreading to others and how to treat it as well. Thanks for the background on this condition. Voted up.
Linda Crampton (author) from British Columbia, Canada on September 11, 2012:
Thanks for the visit, Tom. I appreciate your comment and all the votes!
Thomas Silvia from Massachusetts on September 11, 2012:
Hi my friend, very interesting and informative has always. Thanks for this information i learned a lot reading this hub.
Vote up and more !!!
Linda Crampton (author) from British Columbia, Canada on September 11, 2012:
Thank you so much for the visit and the amusing comment, drbj! I appreciate them both.
drbj and sherry from south Florida on September 11, 2012:
This is such a realistic tratment of conjunctivitis and dry eye syndrome, Alicia, I can feel my eyes getting dryer by the moment. Time out while I go find my artificial tears.
Linda Crampton (author) from British Columbia, Canada on September 11, 2012:
Hi, shara63. It must be a very difficult and unpleasant time for the people in your country who have viral conjunctivitis and waterborne diseases in this rainy season. Thank you very much for your comment. Eyes certainly are a wonderful sense organ!
Farhat from Delhi on September 11, 2012:
AliciaC, thank you for this Informative hub...its rainy season and in India water born diseases are on its peak these days, viral conjuctivitis is one very common among them, specially in remote areas with poor drainage system & water logging problem!
Your hub is a real help in bringing some awareness by taking some preventive measures to stop the spreading of disease from one to the other person. Information on Tears is equally useful, and it gives a wonderful knowledge for how to protect our most precious Gift from God 'the Eyes' ........Its very true, "Eyes are the word " !
Linda Crampton (author) from British Columbia, Canada on September 10, 2012:
Thank you very much for all the votes, Prasetio, and for sharing the hub with your mom! I appreciate your visit. It is important to maintain the health of the eyes. Vision is an important sense.
prasetio30 from malang-indonesia on September 10, 2012:
Very informative hub as always. Eyes are the most important part of the body, we should always care about this. Again...I learn many things from this hub and I'll share with my mom. Thank you very much for writing. Voted up (useful, awesome, interesting). Cheers,