Conjunctivitis causes redness and inflammation of the thin layer of tissue that covers the white of your eye (the conjunctiva). It can be caused by a bacterial or viral infection, an allergic reaction or by your eye coming into contact with an irritant.
During conjunctivitis blood vessels within your eye expand and fill with blood. This causes your eye to turn red and feel sore. Sometimes a yellow discharge can cause your eyelids to stick together.
Conjunctivitis can be very contagious. Treatment depends on what type of conjunctivitis you have. It commonly takes the form of eye drops, antibiotics and antiviral medication.
Many of the symptoms associated with conjunctivitis are easily recognisable.
The most distinct of these is having a red or a pink colour to the white of your eye—your conjunctiva. Another very common symptom of the condition is an itchy, sore or burning feeling as well as your eyes feeling watery. In some cases, you might also experience a sensitivity to light, blurred vision and a swelling of your eyelids.
Discharge (a watery, often foul-smelling, liquid) is another very common symptom of the condition. The type of discharge you have can often help to show what form of conjunctivitis you have. Green or yellow discharge usually indicates bacterial conjunctivitis. A clear, watery discharge usually indicates viral conjunctivitis. A mucus discharge usually suggests allergic conjunctivitis.
There are three main causes of conjunctivitis— infection, allergies and irritants. Bacterial conjunctivitis and viral conjunctivitis are caused by an infection and are normally very contagious.
Irritant conjunctivitis is usually caused by something rubbing against your eye, like an eyelash or piece of dirt. Allergenic conjunctivitis is caused by something coming into contact with your eye that you are allergic to. Both of these forms of conjunctivitis are not normally contagious.
Conjunctivitis affects both men and women equally. It can occur at any age. You're more likely to develop the condition if you've been in contact with someone else who has it.
Conjunctivitis is usually diagnosed by a swab test, taken by your doctor or optometrist.
Treatment isn't normally needed. Most cases will clear up within a few weeks. If your conjunctivitis is very severe though you may be prescribed antibiotic eye drops or antiviral medication.
If you have allergic conjunctivitis, it makes sense to limit your exposure to the allergens that are causing the condition. This form of conjunctivitis will normally clear up once you stop being exposed to the thing that is triggering your allergic reaction. Antihistamines can help to reduce the irritation you feel.
Eye baths and regular cool compresses can also help to alleviate symptoms. Remember to not touch your eyes and wash your hands regularly. This will reduce the risk of passing the condition on to other people.