Conjunctivitis Home A-Z Health Information Health Library A-Z Conjunctivitis Overview The conjunctiva is the transparent membrane that lines the eyelids and eyeballs and protects the white part of the eye and the areas under the eyelids. Conjunctivitis, also known as pink eye, refers to the inflammation of the conjunctiva. Causes Based on the causative agents, there are different types of conjunctivitis:Viral conjunctivitis: Acute (short-term) conjunctivitis is most commonly caused by viruses, especially those belonging to the adenovirus family. Several other viruses, such as the measles or mumps viruses, viruses that cause eye herpes, enteroviruses or coxsackieviruses (cause hand, foot, and mouth disease) (uncommon), or SARS-CoV-2 (causes COVID-19) (uncommon), can also cause pink eye. Viral conjunctivitis tends to cause watering and redness of the eyes and can persist for two to three weeks even after appropriate treatment. Usually, viral conjunctivitis does not affect vision. In rare cases, it may cause the blurring of vision or a glares when looking directly at bright objects. This is due to an inflammatory reaction that results in the formation of small white dots on the cornea (the transparent front layer of the eye). These spots usually go away after a few weeks or sometimes, a few months.Bacterial conjunctivitis: Bacteria are the second most common causes of infectious conjunctivitis. The most common bacteria that cause conjunctivitis are Staphylococcus species (which cause staph infections), Streptococcus species (which cause strep throat and pneumococcal disease), Haemophilus influenzae (which causes meningitis in young children), and bacteria that cause sexually transmitted infections, such as chlamydia, gonorrhoea, and syphilis. Moreover, these conditions may also be passed from the mother to child, leading to neonatal conjunctivitis, a condition that can cause permanent blindness and/or permanent eye damage. Bacterial conjunctivitis is associated with redness in the eyes along with a sticky yellow discharge.Allergic conjunctivitis: Sometimes, the immune system reacts to usually harmless substances like pollen, dust, or grass, causing a non-infectious type of conjunctivitis. This is common in patients with pre-existing allergies or a family history of allergies. The occurrence of seasonal allergic conjunctivitis varies depending on the season and weather conditions. Individuals with pre-existing allergies (e.g., allergies to dust mites, dander (animal fur), and pollen) may display symptoms throughout the year.Other types of non-infectious conjunctivitis: Apart from allergens, other factors/substances may cause conjunctivitis, such as toxic substances or eye irritants (including contact lenses or contact solution, cosmetics or eye products (shampoos and eye makeup), chlorine in swimming pools, smoke, and certain types of medications), injuries that cause conjunctival damage, immune disorders that affect the eye, and conjunctival tumours or cancers. Symptoms Infective conjunctivitis can affect one eye or both eyes. Its symptoms include:Inflammation and redness of the whites of the eyes.Gritty, watery, or sticky eyes, especially in the mornings.Blurred vision due to tears or the formation of a sticky discharge.Flu-like symptoms, such as general malaise, sore throat, muscle aches, and fever. Diagnosis Conjunctivitis is typically diagnosed through a comprehensive eye examination performed by an ophthalmologist. The steps involved in diagnosing conjunctivitis include:Collection of medical history to rule out conjunctivitis (the ophthalmologist asks questions about symptoms, any close contact with other people with conjunctivitis, and possible contact with eye irritants).Slit-lamp examination (to examine various parts of the eye, including the sclera, conjunctiva, iris, and cornea). Visual acuity tests to ascertain whether conjunctivitis has affected the vision.Eye culture (sampling of the cells from underneath the eyelids with a cotton swab for further examination by a pathologist to ascertain the causative pathogen). Preventive measures Bacterial and viral conjunctivitis are highly contagious. They spread very easily via droplets (coughing or sneezing) or contact with fomites, such as tissues, towels, or pillowcases. To avoid the spread of infection, it is important to: Wash hands frequently.Cover mouth while coughing or sneezing.Dispose of tissues after use.Avoid sharing contagious belongings. The following measures may be used to prevent allergic and other forms of non-contagious conjunctivitis: Allergy testing to identify potential triggers. Wash your face after being exposed to allergens like dust or pollen.Keep windows closed during seasons when pollen or fungal spores are abundant. Wash your hands after petting animals.Frequently cleaning the house.Washing bedding/pillows using detergents and hot water.Careful use of medications, cosmetics, and apparatus along with regular consultation with the physician.Monitoring exposure to different activities (such as swimming) and environments (such as polluted areas). Treatment Most cases of infective conjunctivitis require no treatment as the infections are self-limiting and will clear up on their own within a few days to a few weeks. However, if the condition persists, treatment options for infective conjunctivitis include:Antibiotic ointments or eye drops: These may be helpful in managing bacterial conjunctivitis. However, viral infections do not respond to antibiotics and may last for two to three weeks until the natural immunity of the host eliminates the virus.Lubricating ointments, eye drops, or gels: These may help reduce discomfort and grittiness but not the duration of the illness.Over-the-counter and prescription painkillers, such as paracetamol or ibuprofen (provided no medical reason prevents their use) can help alleviate the discomfort and flu-like symptoms associated with conjunctivitis.Warm-water washes: This can be performed routinely to clean the sticky discharge from the eyes.Steroidal eye drops: These are used to reduce inflammation in severe cases.Treatment options include:Avoiding rubbing of the eyes as it worsens symptoms.Cold compress to help reduce eyelid swelling.Application of lubricating ointments or eye drops may help reduce discomfort but will not treat the allergy.Over-the-counter anti-allergy drops need to be used daily. These may require up to two weeks to work. While some people need to use these drops for only a few weeks in the summer, others may have to do so throughout the spring and summer months. However, depending on the severity of symptoms, some patients may also need to use these drop throughout the year.Antihistamine tablets.Steroid eye drops (used in severe cases). Complications Occasionally, viral conjunctivitis can cause keratitis (corneal inflammation) or conjunctival scarring, both of which can affect vision. However, these complications are usually manageable with treatment.