Eye infection (conjunctivitis)

General information

Conjunctivitis is the most common eye infection caused by a virus, bacteria or fungus. The conjunctiva is the outer, transparent membrane on the eye that covers the white of the eye (sclera). An infection of the conjunctiva, conjunctivitis, may be caused by a foreign body in the eye, lower immune resistance, dry eyes or allergies.

An infected eye has discharge and looks watery and red. It may feel there is a foreign body in the eye and the eye may feel itchy. The eyelids may also become swollen.

Other eye infections include:

  • Corneal inflammation (keratitis) A virus (e.g. herpes). The eye is sensitive to light and teary with clear watery discharge.
  • Inflammation of the eyelid (blepharitis)The symptoms include swollen and red eyelids. The condition is often associated with atopy and allergies.
  • IritisThe coloured area of the eye is inflamed and the white of the eye is completely red. The symptoms include pain and sensitivity to light. The pupils may be different in size.
  • Inflammation of the episclera (episcleritis) and the sclera (scleritis) The symptoms of episcleritis include pain, sensitivity to air and redness limited to a sector of the eye.
  • Inflammation of the interior of the eye (endophthalmitis) A serious condition that may lead to loss of vision. Usually, the vision is substantially impaired, the eye is very red and produces a heavy discharge. The condition is usually linked with trauma or an eye operation.
  • Preseptal cellulitis The symptoms include significant swelling around the eye, pain and redness and sensitivity of the eyelids and cheek.
  • Orbital cellulitis A serious condition that may lead to loss of vision or even life. The symptoms include impairment or loss of vision, significant swelling and pain in the eye area, protrusion of the eye and the limited movement of the eye. A general feeling of unwellness. It may be related to the infection of the upper respiratory tract.


Mild conjunctivitis during the flu or a cold usually heals of its own accord without antibiotics in a couple of days. Discharge can be cleared by gently rinsing the eye.

If the conjunctivitis is known to be caused by an allergy, antihistamines will help. The pharmacy staff will help you choose the right products.

When should you seek medical advice?

Seek medical advice if

  • the inflammation does not clear up with self-care in a few days
  • the eye is painful, or your vision is impaired

If your symptoms include significant swelling and redness and heavy discharge, or your general health is poor, it may be caused by endophthalmitis or preseptal or orbital cellulitis. In these situations, you should seek medical help immediately.

This Self-care instruction has been produced in collaboration with Duodecim Terveyskirjasto

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Updated  8.6.2020