Pink eye, also known as conjunctivitis, is an inflammation of the conjunctiva of the eye. The conjunctiva is the membrane of the eyelid and eye surface. If the conjunctiva gets inflamed, it will turn red and swell. The eye may burn and itch and it may feel as though there is something in the eye. Tear production will increase. There are four main causes of pink eye.
Infections
Both bacteria and viruses can cause pink eye. According to the Mayo Clinic, pink eye caused by a bacterial infection will have a yellowish discharge while pink eye caused by a virus will have a watery discharge. Infectious pink eye is very contagious in both children and adults. Respiratory illness can contaminate the eye and cause pink eye. Antibiotics can be used to treat infective pink eye.
Allergies
The Mayo Clinic also says that when exposed to an allergen, the body produces chemicals that cause inflammation. If the allergen is in the eye, the eye turns red and tear production increases. This is called allergic conjunctivitis. This type of pink eye is not contagious. Common allergens include pollen, dust, molds, grasses, animal hair and dander and cosmetics. Proteins that build up on improperly cleaned contact lenses can also cause allergic pink eye. Antihistamine eye drops can be used to treat this type of pink eye.
Chemical Exposure
Ophthalmologist Tissa Senaratne states that exposure to many chemicals causes pink eye. This list includes preservatives used in eye drops themselves. Any chemical that comes into contact with the eye can cause pink eye and result in watery eyes or pussy discharge. This type of pink eye is not contagious. A broad spectrum antibiotic gel made from tetracycline can be used to treat pink eye caused by chemical exposure.
Particle in the Eye
The body reacts to foreign bodies by causing inflammation. If a foreign body gets into the eye, it causes inflammation of the conjunctiva. If the object is contaminated with a virus or bacteria, the pink eye could become infective pink eye. According to David S. Smith, when there is a foreign body in the eye, the eye will water and the person will be able to indicate where the object is. This type of pink eye is not contagious unless there is a secondary infection. The National Eye Institute says if tears do not wash out the particle, you should not try to remove the object as an attempt to remove the particle can damage the eye. The book "Nursing: Interpreting Signs and Symptoms," explains that if the object does not come out with tears, a doctor will carefully remove it and prescribe antibiotic eye drops. (See References 5) The doctor may also prescribe an eye patch to protect the eye during recovery.
