What do you need to know about conjunctivitis

As alarming as it may be to look in the mirror and find bloodshot eyes staring back at you, the likelihood is it’s not as serious as you think. Conjunctivitis is one of the most common causes of eye redness, and will often clear up of its own accord. However, there are occasions where symptoms can be more severe or can point towards signs of something more serious.

So, if this happens to you, it’s best to take some precautions. This article aims to provide a bit of clarification over what conjunctivitis is, how it is caused, what indicators to look out for and what measures you can take to prevent and treat it.

What is conjunctivitis?

Conjunctivitis is the term given to an inflammation of the conjunctiva, which is the thin, transparent membrane that covers the front of the eye and lines the insides of the eyelids. Although it may sound harmful and dangerous, it is a relatively common condition, which can generally be quite easily treated.

You may already know of conjunctivitis by its more colloquial term “red eye”. It is referred to as “red eye” because the condition is characterised by red, bloodshot eyes, which themselves are caused by the dilation and swelling of blood vessels in the conjunctiva. These blood vessels can dilate as a result of various forms of inflammation, and as such there are multiple possible causes of conjunctivitis.


Aside from red eyes, conjunctivitis can come with several other symptoms that may differ depending on the root cause of the inflammation. These symptoms can include:

  • Increased tear flow
  • Itchy, irritable eyes
  • Blurry vision
  • Increased light sensitivity
  • Sore eyes
  • Thick yellow discharge that crusts over the eyelashes

The vast majority of cases of conjunctivitis are likely to be minor and so many of these symptoms probably won't feature. However, if you find you are experiencing symptoms, such as sensitivity to light or irritable eyes, it may be advisable to seek medical advice.

What causes conjunctivitis?

Conjunctivitis can arise from multiple causes, with varying levels of severity:

  • Viruses are a prominent cause of conjunctivitis. Viral conjunctivitis is characterised by irritable eyes and sensitivity to light. It is a highly contagious form of the condition as it can be spread simply through coughing and sneezing, although it will usually clear up of its own accord after a few days without the need for medical treatment.
  • Bacteria is another common cause of red-eye. Cases of bacterial conjunctivitis may feature a yellow discharge in the corner of the infected eye. Again, this is a contagious form of the condition, although it is often passed on through direct physical contact with infected items.
  • Allergens can very easily penetrate the eye. The prime culprits in this category tend to be pollen, dust and pet dander, which cause symptoms such as watery, irritable eyes, along with light sensitivity. In these cases, both eyes are usually affected, although it is not contagious.
  • Aside from the three main causes, there are numerous other irritants that have a habit of working their way into our eyes and causing inflammation. The most prevalent irritants include smoke, dirt and grit, shampoo and chlorine from swimming pools, as well as other rogue particles. A loose eyelash rubbing against the eye can even be a cause.

Who gets conjunctivitis?

Infective conjunctivitis accounts for both the bacterial and viral forms of the condition. Due to the numerous causes of infective conjunctivitis, it is hard to pinpoint who in particular is most susceptible, but there are a few risk groups concerned.

  • Bacterial and viral conjunctivitis

Children, in general, are believed to be more at risk of bacterial and viral conjunctivitis that adults, as their immune system is still developing. This is thought to be because they come into contact with more infections while at school. Similarly, those who work in busy environments or crowded places, are naturally more susceptible as the viruses can be spread through coughing and sneezing. 

A weakened immune system, which is believed to accompany old age, is thought to put the elderly at greater risk. Likewise, those who have recently suffered a cold, or people with diabetes or other conditions that may weaken the immune system, are at higher risk.

Gonococcal and chlamydial conjunctivitis are bacterial forms derived from sexually transmitted infections. They usually find their way into the eye through physical contact after an STI sufferer touches their genital region. Consequently, those having unprotected sex are at higher risk of contracting conjunctivitis than those who are not. A newborn child can suffer neonatal conjunctivitis if the mother has an STI during childbirth.

  • Allergic and irritant conjunctivitis

Typically, allergic conjunctivitis tends to be more common amongst people who suffer from other allergies, such as asthma. It can occur alongside allergic rhinitis, which is when an allergic reaction causes an inflammation of the inside of the nose. Consequently, those who may be exposed to allergens on a regular basis are at higher risk. Certain allergens - notably pollen - are seasonal. As a result, people, in general, are more likely to contract allergic conjunctivitis during the summer months as it is hay fever season.

Due to the matter-of-chance nature of suffering from conjunctivitis as a result of irritants, it is harder to generalise a risk group. However, smokers and those who work in polluted environments without sufficient eye protection will be more susceptible. So too will those who work in a manual job where particles such as dust can get into the eye. Likewise, people who swim often and are frequently exposed to chlorine may suffer from conjunctivitis.

How to prevent conjunctivitis

If our summary of those at risk of conjunctivitis has got you panicking, there is no need to. There are various simple measures you can take to help reduce your risk:

  • Personal hygiene is essential. Wash your hands regularly, especially when you are in public places.
  • Similarly, cleaning surfaces around the house (where bacteria can build up) with an antiseptic cleaner can also help to reduce your risk.
  • Try to avoid touching or rubbing your eyes or the surrounding area.
  • Cover your mouth and nose when coughing or sneezing.
  • Try not to share personal items that will come into contact with your eyes, such as pillows or hand towels.
  • Either avoid wearing eye makeup or ensure that you remove any before settling down to bed.
  • Contact lens wearers must ensure they follow guidelines for lens care and replacement and remove contact lenses before showering or swimming.

How to treat conjunctivitis

Conjunctivitis often won’t require treatment as the symptoms will usually clear up within two weeks. While you may not need to pay the doctor a visit, there are treatments you can use at home to help ease your symptoms.

  • Resting a clean, cool compress over the eyes for 5-10 minutes at regular intervals throughout the day can help to relieve symptoms of viral conjunctivitis.
  • If your eyes are producing a discharge, be sure to gently clean it from your eyelids regularly with soaked cotton wool balls.
  • If you are a contact lens wearer and you find yourself suffering from conjunctivitis, it is imperative that you remove your lenses. If you have worn contact lenses whilst suffering from conjunctivitis, ensure you dispose of them correctly as they can be a source of re-infection.
  • Cases of irritant conjunctivitis are highly unlikely to require special care as treatment is simply a case of removing the irritant. Eyewash solutions are available to aid in flushing out irritants whilst cleansing and refreshing the eye.

However, in more severe instances where treatment is required, the type of treatment will depend on the cause of inflammation:

  • You may be prescribed antibiotics which can take the form of eye drops or ointment.
  • Allergic conjunctivitis may require antihistamines, which help prevent symptoms of allergic reactions by helping to prevent the release of histamine. Antihistamine eye drops are available, as are oral antihistamines. Both of which can offer effective relief.

Optrex Allergy Eye Drops contain sodium cromoglicate and can be used to treat acute seasonal and perennial allergic conjunctivitis. 


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