Infective conjunctivitis is an infection of the conjunctiva (the front skin of the eye). It is very common. One or both eyes become red or pink, they may be sticky or watery and may have surface irritation. Most cases clear in a few days without any treatment. Antibiotic drops or ointments may be advised if the infection is severe or does not settle. Marked eye pain, light hurting your eyes and reduced vision are not features of common infective conjunctivitis. Tell your doctor if these or other worrying symptoms develop. Conjunctivitis in a newborn baby is different to the common 'sticky eye' of newborn babies, and needs urgent attention from a doctor.
What is conjunctivitis?
Conjunctivitis means inflammation of the conjunctiva. The conjunctiva is the thin covering (like a very thin skin) that covers the white part of the eyes and the inside of the eyelids.
What causes conjunctivitis?
- Infection is the most common cause.
- Allergy is another common cause. Many people with pollen allergy (hay fever) have red and inflamed conjunctiva (the thin covering of the white part of the eyes and inside of the eyelids).
- Irritant conjunctivitis sometimes occurs. For example, your conjunctiva may become inflamed after getting some shampoo in your eyes. The chlorine in swimming baths is a common cause of mild irritant conjunctivitis.
For more details on conjunctivitis related to an allergy or irritant, see the separate leaflet called Allergic Conjunctivitis.
The rest of this leaflet is about conjunctivitis caused by infection.
Types of infective conjunctivitis
Common infective conjunctivitis
Most cases of infective conjunctivitis are caused by common germs (bacteria and viruses). These are often the same ones that cause coughs and colds. Conjunctivitis commonly develops when you have a cold or cough. although sometimes it occurs alone. In the vast majority of cases, infective conjunctivitis is not serious. It clears within a week or so without leaving any permanent damage to the eye.
More serious types of infective conjunctivitis
Rarely, infective conjunctivitis is more serious. For example:
- Conjunctivitis may develop in addition to infection of the cornea (keratitis). The cornea is the transparent front part of the eye. This is most commonly due to an infection with the cold sore virus (the herpes virus). If you have keratitis you are likely to get eye pain rather than just surface irritation. Blurring of vision is also common.
- A virus called adenovirus can sometimes cause a serious and prolonged conjunctivitis.
- Conjunctivitis in newborn babies can be caused by germs called chlamydia or gonorrhoea. These are serious sexually transmitted infections and need urgent treatment if they affect the eye of babies. (If a mother has one of these infections in her vagina, it can be passed on to the eye of their baby during childbirth.) Note: this is different to the very common sticky eye of newborn babies, caused by a blocked tear duct. A blocked tear duct with sticky eye does not cause redness and inflammation of the conjunctiva. See separate leaflet called Tear Duct Blockage in Babies for details.
- Some adults develop conjunctivitis due to chlamydia.
- Conjunctivitis can sometimes be just one part of a more serious infection of deeper structures of the eye. This may be indicated by eye pain, reduced vision, or swelling around the eye.
What are the symptoms of common infective conjunctivitis?
- Infective conjunctivitis usually spreads to both eyes. The whites of the eyes look inflamed, and red or pink.
- The eyes may feel gritty and may water more than usual.
- Some mild soreness may develop, but the condition is not usually very painful.
- The eyelids may become swollen. They are often stuck together with gluey material (discharge) after a sleep.
- Vision is not normally affected. You may get some blurring of vision due to discharge at the front of the eye. However, this clears with blinking.
What is the treatment for common infective conjunctivitis?
- Not treating - this is a common option for mild or moderate infections. Your tears contain chemicals that fight off germs (bacteria). Without treatment, most cases of infective conjunctivitis clear on their own within 1-2 weeks. Often they clear within 2-5 days. If symptoms get worse then see a doctor to check your eye and to see if you need treatment.
- Bathing the eyes - using cool clean water, this may be soothing.
- Lubricant eye drops - these may reduce eye discomfort. They are available over the counter, as well as on prescription.
These may be prescribed. This might be:
- An eye drop such as chloramphenicol.
- Eye ointment such as chloramphenicol or fusidic acid (actually an oily drop, halfway between an ointment and a drop).
Note: treatment using antibiotic preparations tends to be for more severe cases. It is also used for those cases not clearing on their own. (Tell your doctor if you are pregnant, as some eye drops may not be suitable.)
Other general advice
- Do not wear contact lenses until symptoms have completely gone, and for 24 hours after the last dose of any eye drops or ointment.
- You can clean secretions from eyelids and lashes with cotton wool soaked in water.
- Infective conjunctivitis is contagious, which means it can be passed on by touching. The likelihood of passing it on is not high unless you are in close contact with others. However, until the infection has gone, to help prevent passing it on:
- Wash your hands regularly, particularly after touching your eyes.
- Do not share towels, pillows or utensils.
What should I look out for?
See a doctor if symptoms change, or do not settle within a few days, or if you are concerned that you have anything other than a common conjunctivitis. In particular, see a doctor urgently if:
- You develop marked eye pain.
- Light starts to hurt your eyes (photophobia).
- Spots or blisters develop on the skin next to the eye.
- Your vision becomes affected.
- Your newborn baby develops conjunctivitis.
Most conjunctival infections are not serious, do not harm the eye, and clear in a few days. However, some infections such as herpes or chlamydia persist for longer than usual, are more serious, and need special treatment. Most serious eye infections cause significant pain and many also affect vision. Some other conditions, including allergic conjunctivitis can appear similar to infective conjunctivitis initially. This makes it particularly important that you go back to your doctor if things get worse or if they do not settle as expected.
Does a child with conjunctivitis need to stay off school?
Guidance from Public Health England (PHE) (the Health Protection Agency) states that it is not necessary to exclude a child from school or from childcare if they have infective conjunctivitis, unless there is an outbreak of several cases. If an outbreak occurs, the school or childcare centre should seek advice from the PHE or other health professional.
Dr Tim Kenny
Dr Mary Lowth
Dr Helen Huins