Conjunctivitis is a common eye infection. Even if it can get very uncomfortable, it has no risk of altering your vision without complication. Commonly referred to as pink eye, you can prevent it, but how do you recognize symptoms of conjunctivitis in other cases? A few different observations can help you pinpoint the causes.

Definition of conjunctivitis

Conjunctivitis is an inflammation of the conjunctiva. This part of the eye is the membrane that covers the sclera (white of the eye) and the inside of the eyelid. Its primary function is to lubricate the eye to avoid dryness and to protect it from external aggressions.

Causes and symptoms

Conjunctivitis can be attributed to four main causes. In any case, it is best to consult a health professional.

Viral origin

Caused by a virus, viral conjunctivitis is very contagious. In addition to causing redness in the eye and a tingling sensation that makes it seem like a foreign object is lodged in your eye, it is common to see transparent liquid and translucent secretions sometimes paired with a sore throat. It is not uncommon for this viral infection to develop with a cold or an eruptive disease. This variant is often seen in children. It is the most common form of conjunctivitis in adults, and it usually affects both eyes simultaneously.

Bacterial origin

As the name suggests, bacterial conjunctivitis appears when a bacterium (streptococcus or staphylococcus) is present. Unlike viral conjunctivitis, it usually affects only one eye at a time. Less common than the others, it is recognized mainly by the presence of swollen eyelids and yellow and thick secretions. These symptoms are in addition to the feeling of irritation and foreign objects in the eye. It is most often found in children.

Allergic origin

Allergic conjunctivitis occurs mainly when spring begins, often during spring and summer when there are allergens in the air, including pollen.

Associated with allergic rhinitis, this type of conjunctivitis occurs when the person comes into contact with the pollen to which they are allergic. Affecting both eyes, the most common symptoms are swollen eyelids, itchy and watery eyes. This seasonal inflammation often recurs at the same time each year, depending on the allergen responsible.

Allergies to animal fur or dust mites are also a cause of allergic conjunctivitis. In this case, conjunctivitis is likely to persist as long as the person is in contact with the allergen.

Irritative origin

Several irritants are present in everyday life, such as smoke, dust, chemicals or any foreign objects that can irritate. Usually, irritative conjunctivitis affects both eyes and symptoms may resemble viral conjunctivitis: redness, tingling, a foreign body sensation or dry eye. This condition is not contagious, however. A feeling of dryness in the eye will also be present with redness and superficial pain in the eye.


As in many cases of eye conditions, prevention is possible and desirable. Several small actions will allow you to reduce your chances of contracting conjunctivitis according to the different types of conjunctivitis mentioned above. For allergic and irritative conjunctivitis, the logic of prevention would be to limit exposure to substances causing inflammation.

Try not to:

  • Allow air to enter the car during high allergen seasons
  • Be in contact with animals that you are allergic to
  • Smoke cigarettes or find yourself near smoke
  • Do any gardening or mowing the lawn when the allergens are high
  • Apply makeup that is hypoallergenic if possible
  • Avoid wearing contact lenses when symptoms are severe
  • Wear eye protection when in contact with any products or objects that could harm your eyes.
  • Wearing protective glasses can help reduce exposure to substances that can cause conjunctival reactions, in addition to protecting against the intrusion of foreign objects.

Bacterial or viral conjunctivitis are contagious; Hygiene, therefore, remains the best way to prevent their spread. Small changes in your lifestyle can go a long way in preventing contaminating your eyes:

  • Avoid rubbing your eyelids or putting your fingers in your eyes
  • Wash your hands before each manipulation near the eye (ex: putting on contact lenses)
  • Throw away products that could have been contaminated by previous conjunctivitis (ex: makeup)
  • Also, avoid sharing these products or accessories with other people
  • Replace the use of contact lenses with your glasses for the duration of your conjunctivitis treatment
  • Wash your hands regularly

Regardless of the type of conjunctivitis symptoms you have, we advise you to consult your Optometrist as soon as possible. If you want to make an appointment with one of our IRIS eye care professionals, know that it is possible to book your appointment here.