Conjunctivitis, also called "pinkeye" in the United States and "madras eye" in India, describes the inflammation or infection of the transparent membrane that lines the eyelid (conjunctiva) and part of the eyeball.
Conjunctivitis can be caused by an infection, allergic reaction, or exposure to chemicals or irritants.
Common symptoms include redness, tearing and itching in one or both eyes, blurred vision, sensitivity to light, feeling of grittiness in one or both eyes, and discharge in one or both eyes.
The name "madras eye" originated when the adenovirus, a virus that causes conjunctivitis, was first identified in Chennai (Madras), India during the early 20th Century.
Even though conjunctivitis that is caused by an infection is highly contagious, it does not cause serious health problems if it is diagnosed and treated early. However, if left untreated, it can lead to serious eye damage, including permanent vision loss.
Blepharoconjunctivitis is a combination of conjunctivitis and inflammation of the eyelids (blepharitis). Keratoconjunctivitis is a combination of conjunctivitis and inflammation of the cornea (keratitis).
Conjunctivitis that is caused by an infection is treated with antibiotics or antivirals. Patients who have allergic conjunctivitis are typically treated with antihistamines, ocular (eye) decongestants, and mast cell stabilizers. These medications are available as eye drops, eye creams, and oral pills.
Allergy: Allergic conjunctivitis, which effects both eyes, occurs in response to an allergy-causing substance like dust mites or pollen. This form is not contagious. The thin membrane that covers the eyelids and the exposed surface of the eyes is part of the immune system, and it can react to airborne allergens.
Typically, an allergic response is not triggered the first time the body encounters the allergen. The immune system may become sensitized the first time or several times after the body is exposed to an allergen. During this process, the body's white blood cells develop immunoglobulin E (IgE) antibodies to the allergens. Once sensitized, the antibodies quickly detect and bind to the allergens in the body. These antibodies also trigger the release of chemicals (like histamine) that cause allergic symptoms, including red, watery, itchy eyes.
Some cases of allergic conjunctivitis may be seasonal if they are caused by seasonal allergens, such as mold, pollen, and grass.
Cases that do not show seasonal variation are called perennial allergic conjunctivitis. This condition can occur at any time. It may be triggered by allergens like perfumes or protein deposits on the contact lenses.
Bacterial: An infection caused by bacteria like staphylococcus or streptococcus may cause conjunctivitis. Bacterial conjunctivitis is highly contagious. If the bacteria are present on the skin, it may spread to the eyes where it causes conjunctivitis. The bacteria can also be spread from sharing eye makeup or contact lenses or after touching or rubbing the eyes with dirty hands. This form is more common among children than adults.
A bacterial infection with chlamydia can also cause conjunctivitis. While this type of bacterial conjunctivitis is uncommon in the United States, it is prevalent in many Middle Eastern and African countries. Chlamydia is a sexually transmitted infection.
Viral: Viral infections are responsible for most cases of conjunctivitis. This type is highly contagious. Many of the viruses that cause the common cold can also lead to conjunctivitis. The adenovirus, which is prevalent during the rainy season or winter months, may also cause viral conjunctivitis.
Chemicals and irritants: Conjunctivitis may also be caused by exposure to certain chemicals and irritants. For instance, irritant gases like chlorine or hydrochloric acid, natural toxins like ricin, or splash injuries from chemicals may lead to conjunctivitis. This type of conjunctivitis is not contagious.
Other: Other causes of conjunctivitis include ultraviolet burns, overuse of contact lenses, foreign objects, vitamin deficiency, exposure to chickens infected with Newcastle disease, pre-cancerous cells, and some conditions of unknown cause like sarcoidosis (disease that causes lesions to develop in the lungs, liver, spleen, skin, eyes, and lymph nodes). None of these types of conjunctivitis are contagious.
General: Conjunctivitis symptoms and signs are generally nonspecific. Redness, irritated and watery, itchy eyes, blurred vision, and discharge that forms a crust during sleep are common symptoms of conjunctivitis. Other less common symptoms may include pain and sensitivity to light.
Allergic: Allergic conjunctivitis affects both eyes. The eyes become extremely itchy and the eyelids swell. This form causes edema (swelling caused by excess water in the tissues) of the conjunctiva and sometimes the whole eyelid. The eyes may also secrete a mucus discharge.
Bacterial: Bacterial conjunctivitis usually affects one eye at first and often spreads to the other. Common symptoms include a feeling of grittiness in the eyes, irritation, reddening of the eyes and a thick yellow-green discharge that may cause the lids to stick together, especially after sleeping. This condition may be associated with a sore throat or lung infection (like pneumonia).
Viral: Viral conjunctivitis usually starts with one eye and often spreads to the other. Viral conjunctivitis is usually associated with upper respiratory (lung) infection, a common cold, or sore throat. Common symptoms include watery eye discharge and itchy eyes.
Chemicals and irritants:
Irritant or toxic conjunctivitis is usually painful and it may cause reddening of the eyes. The eyes may secrete mucus.
General: Although tests are available to diagnose the specific cause of conjunctivitis, a diagnosis is typically made after a physical examination and medical history. A slit lamp exam can confirm a diagnosis. A sample of the patient's eye discharge may be cultured to determine whether a bacteria or virus is the cause. A skin test or antigen-specific immunoglobulin (IgE) test may be performed to determine whether the patient is allergic to specific substances.
Slit lamp exam: The slit lamp is a microscope with a light that helps the eye doctor observe the eye under high magnification. The doctor is able to see the front and the back of the eye.
Culture: A sample of the patient's eye discharge may be cultured. When a bacterial or viral infection is suspected, the sample is placed on a Petri dish and allowed to grow in a laboratory. If a bacteria or virus is causing conjunctivitis, it will grow on the Petri dish.
Skin test: A skin test is used to determine whether a patient is allergic to certain substances. During the test, the skin is exposed to different allergens. The skin is then observed for an allergic reaction. If an allergen triggers an allergic reaction to a test, the patient will develop reddening, swelling, or a raised, itchy red wheal (bump) that looks similar to a mosquito bite. The healthcare provider will measure the size of the wheal and record the results. The larger the wheal, the more severe the allergy. A skin test is typically conducted in a healthcare provider's office. Skin tests cause minimal, if any, discomfort. The needles used barely penetrate the skin's surface and will not cause bleeding.
Allergen-specific immunoglobulin (IgE) test: An allergen-specific immunoglobulin E (IgE) test, commonly referred to as radioallergosorbent test (RAST®), may also be used to determine whether the patient is allergic to specific substances. However, this test is less accurate than a skin test. It is usually performed in patients who have coexisting severe skin diseases (like eczema or psoriasis) that make it difficult to interpret a skin test.
The in vitro test is conducted in a laboratory. During the procedure, a sample of blood is taken from the patient. The blood is then sent to a laboratory that performs specific IgE blood tests. The allergen is bound to an allergosorbent (paper disk). Then the patient's blood is added. If the blood contains antibodies (immunoglobulins that detect and bind to antigens) to the allergen, the blood will bind to the allergen on the disc. A radiolabelled ANTI-IgE antibody is then added to the disc to measure the level of immunoglobulin E present in the blood. The higher the radioactivity, the higher the level of IgE in the blood and the more severe the allergy.
A qualified healthcare provider will interpret the results of the test. In general, the sensitivity of these tests range from 50-90%, with the average being about 70-75%. The patient will receive test results in about seven to 14 days.
General: Treatment of conjunctivitis depends on the cause of the infection. Patients who have bacterial or viral conjunctivitis in one eye may be prescribed medication for both eyes. This helps prevent the infection from spreading.
If conjunctivitis is caused by a chemical or irritant, the affected eye, including under the eyelid, should be flushed with saline. Some patients may also need topical steroids. Some chemicals can severely damage the eye, leading to vision loss, scarring, or surgical removal of the eye.
Patients should tell their healthcare providers if they are taking any drugs (prescription or over-the-counter), herbs, or supplements because they may interact with treatments. Patients should take out their contacts before applying medicine to the eyes. Refrigerating medicated eye drops may help temporarily soothe eye discomfort.
Allergen immunotherapy: Allergen immunotherapy, also known as allergy shots, has been used to reduce symptoms of allergic conjunctivitis. Allergen immunotherapy involves injecting increasing amounts of a diluted allergen into a patient over several months.
There are two phases of immunotherapy -
the build-up phase and the maintenance phase. During the build-up phase, allergy shots are injected into the upper arm once or twice a week for several months (typically three to six months). The dose is gradually increased until the maintenance dose is reached. The maintenance phase begins once the effective therapeutic dose is reached. This dose is different for each patient because it depends on the patient's level of allergen sensitivity and their response to immunotherapy during the build-up phase. Once the maintenance dose is reached, the patient will continue therapy every two to four weeks for two to five years or more. Immunotherapy does not cure allergies, but it may help reduce the body's sensitivity to certain substances.
Antihistamine eye drops: Antihistamines reduce swelling, redness and itching by blocking histamine, the chemical that causes many allergy symptoms. These medications provide quick relief, but the effects usually only last a few hours. Over-the-counter antihistamine eye drops like ketotifen ophthalmic solution (Zaditor®) and antazoline phosphate (Vasocon-A®) have been used to treat allergic conjunctivitis. Antihistamine eye drops like olopatadine ophthalmic (Patanol®) are available by prescription. These medications may cause mild burning or stinging when they are first applied to the eyes.
Antibiotics: Antibiotics may be prescribed to treat bacterial conjunctivitis. Commonly prescribed antibiotic eye drops include sodium sulfacetamide (Bleph-10®, Cetamide®, AK-Sulf®), ciprofloxacin (Ciloxan®), and ofloxacin (Ocuflox®). Commonly prescribed topical antibiotics, which are applied to the lower eyelid, include erythromycin ointment (E-Mycin®), bacitracin (AK-Tracin®, Baciguent®), trimethoprim and polymyxin B (Polytrim®), and Neomycin (Mycifradin®). Oral antibiotics like erythromycin (Ery-Tab®, Erythrocin®) and doxycycline (Bio-Tab®, Vibramycin®, Doryx®) have been used to treat conjunctivitis that is caused by chlamydia. Treatment generally lasts one to three weeks.
Antivirals: Antivirals may be prescribed to treat viral conjunctivitis. Commonly prescribed antiviral eye drops include Trifluridine (Viroptic®) and Acyclovir (Zovirax®). Treatment generally lasts one to three weeks.
Cool compress: A cool compress that is applied to the eyes may help alleviate mild symptoms of allergic conjunctivitis.
Mast cell stabilizers: Mast cell stabilizers like cromolyn (Crolom®) may help alleviate mild symptoms of allergic conjunctivitis. The drug prevents the body from releasing histamine, which is a chemical that triggers allergic symptoms. Cromolyn is most effective if taken before allergy symptoms develop. Patients may experience mild burning or stinging of the eyes. Less common side effects include dryness of puffiness around the eyes and tearing or itching of the eyes. Rare side effects include rash or redness around the eyes, swelling of the membrane that covers the eye, or additional eye irritation that was not present when conjunctivitis was diagnosed.
Ocular (eye) decongestants: Ocular decongestants reduce redness by constricting small blood vessels in the eye. Eye drops like naphazoline lubricant eye drops (Clear Eyes®, AK-Con®, or Opcon®), tetrahydrozoline (Visine AC®), and pheniramine maleate (Opcon-A®) are available over-the-counter and have been shown to help alleviate symptoms of conjunctivitis. Side effects are uncommon. However, long-term use may worsen symptoms. Overuse may lead cause the eyes to become red.
Steroidal eye drops: When conjunctivitis does not respond to other medications, steroidal eye drops like prednisolone (AK-Pred®, Pred Forte®) may help to relieve symptoms. These medications may also be prescribed if the conjunctivitis is caused by chemicals or irritants. These eye drops are only available by prescription and should be taken under the strict supervision of a qualified healthcare provider. These drops may increase the risk of cataracts (clouding of the eye lens), which can cause long-term damage and impaired vision. Common side effects include temporary stinging, burning of the eyes, or blurred vision.
Warm compress: A warm compress may help alleviate discomfort associated with bacterial or viral conjunctivitis. Patients can soak a clean cloth in warm water. The excess water is wrung out, and the cloth is applied to the patient's closed eyes.
Povidone-iodine solutions appear to have broad-spectrum activity against bacteria and have been used in the management of childhood bacterial conjunctivitis. Povidone-iodine solutions may also be used for ophthalmia neonatorum, a type of bacterial conjunctivitis with eye discharge that occurs during the first month of life, and may be as effective as other anti-bacterial solutions such as neomycin-polymyxin B-gramicidin. Medical supervision is recommended and povidone-iodine solutions are not an effective treatment for viral conjunctivitis.
Reactions can be severe and deaths have occurred with exposure to iodine. Avoid iodine-based products if allergic or hypersensitive to iodine. Do no use for more than 14 days. Avoid Lugol solution and saturated solution of potassium iodide (SSKI, PIMA) with hyperkalemia (high amounts of potassium in the blood), pulmonary edema (fluid in the lungs), bronchitis, or tuberculosis. Use cautiously when applying to the skin because it may irritate/burn tissues. Use sodium iodide cautiously with kidney failure. Avoid sodium iodide with gastrointestinal obstruction. Iodine is safe in recommended doses for pregnant or breastfeeding women. Avoid povidone-iodine for perianal preparation during delivery or postpartum antisepsis.
Unclear or conflicting scientific evidence:
Eyebright: Eyebright has been used in eye solutions for centuries to manage multiple eye conditions. Currently, there is insufficient scientific evidence to recommend for or against the use of eyebright in the treatment of conjunctivitis.
Avoid if allergic to eyebright, any of its constituents or members of the Scrophulariaceae family. Use cautiously as an eye treatment, particularly homemade preparations, due to the risk of infection if it is not sterile. Use cautiously with diabetes and drugs that are broken down by the liver. Avoid if pregnant or breastfeeding.
Wash hands often with soap and water, especially after coming in contact with an individual who has bacterial or viral conjunctivitis.
Wash bed linens and pillowcases regularly with hot water and soap to reduce allergens.
Do not share eye makeup, contact lenses, or washcloths with other individuals.
Wash hands thoroughly with soap and water before handling contact lenses. Properly clean contact lenses before wearing them.
Wash hands thoroughly with soap and water before applying eye drops or ointment.
Individuals who are diagnosed with contagious conjunctivitis (caused by a virus or bacteria) should minimize contact with others until they begin treatment and symptoms start to improve. This will help reduce the chance of spreading the infection to others.
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.