The conjunctiva is a clear, mucousy membrane that covers the white part of the eye (the sclera) as well as the inner part of the eylids. The function of the conjunctiva is to produce mucus and water to lubricate the eye.
What is conjunctivitis?
Conjunctivitis, also known as “pink eye”, is inflammation of the conjunctiva. This inflammation can cause uncomfortable symptoms including redness, itching and swelling. Most commonly, conjunctivitis is caused by infection or allergic reactions.
Conjunctivitis is an inflammation of the mucousy covering on the front of the eye that typically causes a red eye as shown in the diagram
What exactly is inflammation?
Inflammation is the first response of the immune system to infection or irritation. When a tissue becomes inflamed, it becomes swollen, red, warm and sometimes painful. If inflammation is severe enough, it can cause the tissue to not function properly.
What are the most common types of conjunctivitis?
There are several types of conjunctivitis; these are grouped according to the cause of the condition. The 3 most common types of conjunctivitis are:
• Bacterial conjunctivitis: bacterial conjunctivitis is caused by bacteria infection; frequently these bacteria are from the patient’s own skin. The condition can affect one or both eyes at the same time and causes a thick, greenish discharge.
• Viral conjunctivitis: viral conjunctivitis is caused by contagious viruses; many of these are the same viruses that cause the common cold; thus, viral conjunctivitis usually occurs along with a cold. Usually viral conjunctivitis affects 1 eye to start, but often will spread to the other eye, as it is so contagious. It causes the eye to tear and give off a light discharge.
• Allergic conjunctivitis: allergic conjunctivitis is a frequent condition for people seasonal allergies to pollen or ragweed. As well, people may have allergic reactions to cosmetic products or drugs. Allergic conjunctivitis affects both eyes at the same time, and also may cause swelling of the eyelids.
What are some other causes of conjunctivitis?
Bacterial conjunctivitis, viral conjunctivitis and allergic conjunctivitis are the most common forms of conjunctivitis. However, there are many other causes for the condition. These include:
• Fungus or parasite infections • Overuse of contact lenses • Gases or chemicals splashed in the eye (especially alkaline chemicals) • Burns to the eye • Autoimmune diseases (this is when the body’s immune system recognizes tissue as foreign an mounts an immune response against that tissue, causing inflammation) • Eye injury • Dry eye
What are symptoms of conjunctivitis?
The symptoms caused by conjunctivitis depend greatly on the cause for the condition. Some common symptoms of conjunctivitis include:
• Pink or red looking eye • Itching • Pain • Avoidance of light • Swollen eyelids • Sticky discharge from the eye (this is usually worse in the morning)
If you think you might have conjunctivitis, you should see a doctor as soon as possible. In most cases, conjunctivitis will not cause permanent damage to the eye; however, there are other eye diseases with similar symptoms that can cause irreversible damage to the eyes.
The picture shows the red eye appearance of a patient with conjunctivitis
How is conjunctivitis treated?
The treatment of conjunctivitis depends on the cause of the inflammation.
Usually, viral conjunctivitis goes away within a matter of 5-10 days and does not require any medications.
In contrast, bacterial conjunctivitis can be treated effectively with antibiotic drops, which help to rid of bacteria in the eye.
Mild cases of allergic conjunctivitis can sometimes be improved with artificial tears; however, more severe cases may require antihistamine eye drops.
If the conjunctivitis is due to contact lens overuse, the best treatment is to avoid wearing contact lenses for a few days.
Is conjunctivitis contagious?
Both viral and bacterial conjunctivitis are contagious. If you have conjunctivitis is one eye, or have a family member or friend with conjunctivitis, you should take extra care to wash your hands frequently, avoid contact with the affected eye, as well as not sharing towels and pillows.
How can I avoid conjunctivitis?
Certain forms of conjunctivitis, such those caused from infection, are contagious and can be avoided by good hand washing and avoiding contact with people with the condition. As well, it is a good idea to not wear contact lenses excessively.
