The conjunctiva is a thin layer of skin that covers the inside of your eyelids and the white (sclera) of your eye. The conjunctiva produces mucus to lubricate the eye and protect it from bacteria and other irritants. Conjunctivitis is an inflammation of the conjunctiva.
Symptoms include redness, itching, a gritty feeling, eye pain, and light sensitivity. Discharge is common and may be watery or very thick, depending on the cause. This may cause hazy vision. Morning crusting frequently occurs.
Conjunctivitis has many different causes, including infections. Viruses are the most common cause of “pink eye.” Other viral symptoms such as sore throat, fever, and runny nose are often present. Symptoms last for up to two weeks. No effective medical treatment shortens the course of the disease but medications can help decrease discomfort. These infections are highly contagious, often affecting both eyes within a day or two. The disease is contagious from just before the discharge begins until it stops.
Bacterial conjunctivitis tends to produce a thicker discharge than viral infections. These infections are also contagious but are usually less easily spread than viral infections. These infections also improve without treatment, but antibiotic drops are effective to shorten the course and prevent spread.
Compresses with warm washcloths can be applied to the lids to loosen crusts from infectious conjunctivitis due to viruses or bacteria. Artificial tears are available over the counter and can be used to soothe the eyes. Good hygiene helps prevent the spread of this disease. Do not share cosmetics and replace contaminated cosmetics. Do not wear contact lenses with an active eye infection and care for your lenses as directed to prevent infections. Do not share towels and change pillowcases frequently. When wiping the eye, do not use the same tissue for the other eye. Discard contaminated tissues immediately in a waste receptacle. Keep your hands away from the eyes and wash your hands often.
When your eyes are exposed to anything to which you are allergic, histamine is released causing intense itching, redness, and tearing. The eyelids may become swollen and rubbing the eyes makes the symptoms worse. Allergies tend to run in families and are associated with asthma and hay fever. Allergic reactions that are due to pollens are seasonal, while dander-related allergies occur year round. Avoidance of the allergen is the best treatment, but this may not be practical in the case of air-borne allergens. Cool compresses to the eyes can soothe them, as can the use of artificial tears. Antihistamine drops are highly effective and are available over the counter. Oral antihistamines can also be used for relief. For severe reactions, steroid eye drops can be prescribed.
A particular type of allergic conjunctivitis, giant papillary conjunctivitis, occurs in contact lens wearers. This reaction is due to development of an allergy to a material in the contact lens, chemicals in the cleaning solutions, or to components in deposits that form on the lens. As the contact lens moves with blinking, it rubs against the underside of the eyelid causing it to become red, rough, and swollen. Sometimes the contact lens will ride up on the eye during a blink. Extended wearing time and poor cleaning can lead to giant papillary conjunctivitis. For mild cases, contact lens use can be continued with modification in the wearing schedule. For severe cases, contact lens wear should be discontinued for a minimum of 2 weeks. Antihistamine and steroid drops can be used to reduce swelling and itching. Changing the lens type to a daily disposable lens can resolve the symptoms. In about 20% of patients who develop giant papillary conjunctivitis, the condition recurs, and discontinuation of contact lens wear is necessary to resolve the condition.