This condition causes the eyes of the patient to become red, itchy and watery or that the conjunctiva of the patient’s eyes has become inflamed. Conjunctiva is the thin covering of the white part of the eyes as well as the inside of the eyelids. One of the most common causes of this condition is an allergic reaction to pollen especially during hay fever season. Another reason is infection of the eyes.
Other least common causes would include irritants such as shampoo getting into the eyes, or chlorine in the swimming pool, allergic reaction to dust mites, contact lenses, some bacterial and viral strains, and cosmetics. The usual medicines are eye drops to alleviate the symptoms. But the symptoms of allergic conjunctivitis should not cause the patient eye pain, reduced vision nor should light hurt the patient’s eyes. Should the patient feel any of these symptoms, then consult a doctor immediately as it may cause other eye conditions.

Causes of Allergic Conjunctivitis

When a person’s immune system over-reacts to chemical substances that get into the body, it may result to inflammation. This is also called allergy and it may cause any of the following:

  • Seasonal conjunctivitis caused by moulds and pollens. Seasonal conjunctivitis occurs at a particular time every year or in a season. Most cases of seasonal conjunctivitis happen during hay fever season due to pollen, particularly grass pollen during early summer. The symptoms may last for a few weeks to one season in one year. Some patients will have recurring hay fever throughout the year. Aside from inflammation of the conjunctiva during hay fever, other symptoms for the condition, such as runny nose or sore throat can also occur.
  • Perennial conjunctivitis. This is the type of conjunctivitis that lasts year round. This caused by dust mites which are creatures that live in the homes of people. It thrives mainly in the mattresses of the bedrooms. Patients who have perennial conjunctivitis may also have perennial allergic rhinitis. Perennial allergic rhinitis has symptoms such as runny nose and sneezing. The symptoms for this condition are at the worst when the patient wakes up in the morning.  
  • Allergies to animals. Some of the patients acquire allergic conjunctivitis when they come in contact with animals.
  • Giant papillary conjunctivitis. This is a very rare condition where the conjunctiva of the upper lid is inflamed. This happens to people with foreign bodies in their eyes such a contact lens. This condition affects one in every one hundred people who wear contact lenses. The cause is not yet understood but it may be caused by some allergic reaction to dust or debris behind the lens. This may also be caused by poor hygiene. This condition can also occur after an eye surgery.
  • Contact conjunctivitis. Some patients are sensitized because of cosmetics, eye drops or make-up that touch or contact the conjunctiva. This contact may cause allergies and conjunctivitis. The eyelids of the patient become inflamed. This condition is sometimes called as contact dermatoconjunctivitis.

Symptoms for Allergic Conjunctivitis

  • Both of the eyes become affected and hasten the development of the condition.
  • The infected eye is itchy, and the white part of the eyes becomes red or sometimes pink.
  • A burning sensation may happen but the infected eye should not feel severe pain.
  • The infected eyelids may become swollen.
  • The eyes become watery and feel dry and gluey like infective conjunctivitis.
  • Vision of the patient should not be affected.
  • The conjunctiva in the upper eyelids can become swollen during severe cases

Complications for Allergic Conjunctivitis

Perennial and seasonal conjunctivitis is unpleasant but the complications that arise are rare. Contact dermatoconjunctivitis and papillary conjunctivitis can cause inflammation of the cornea and ulceration of the cornea or keratitis. This may cause permanent lack of vision if the patient does not submit to treatment.

Treatment of Allergic Conjunctivitis

  • General measures
    • For patients who wear contact lenses, refrain from wearing them until all the symptoms of the condition has gone or wait for twenty-four hours after applying eye drops or eye ointment. But some optometrist can recommend eye drops while wearing contact lenses.
    • Rubbing the eyes can cause severe inflammation.
    • Patting the eyes with cloth soaked in lukewarm water may ease the symptoms.
    • Avoiding the cause of allergy can help a lot. Try staying indoors when you have hay fever to avoid pollens. Close the windows or wear glasses to protect the eyes from infection or dust.
  • Treatment for perennial, seasonal  and conjunctivitis caused by animal contact
    • No treatment can be used by the patient is the symptoms of the condition is mild.
    • The use of eye drops is common to alleviate the symptoms of the condition. There are two types of eye drops: anti-histamine and mast cell stabilizer. Both products produce allergic reactions to counter the chemical histamine which is responsible for allergic reactions. There are various brands of available eye drops in the market. Eye drops should be used regularly until the symptoms are gone. It may take several days before the effect of the eye drop could be seen.
    • Anti-histamine tablets can be taken to ease symptoms of hay fever. These tablets can also alleviate symptoms for conjunctivitis but does not work as well as eye drops. The side effect of this tablet causes drowsiness.
    • Steroid eye drops can also be used but are very rarely prescribed. These eye drops are good with reducing the inflammation but they should only be prescribed if other treatments have failed. Steroids can also make other symptoms of conjunctivitis and other eye problems even worse.
    • Steroid tablets can be used for three to five days when the symptoms are severe. These tablets work very well but taking them in regularly is not advised because possible side effects may occur during long time use.
    • Always tell the doctor if you are pregnant because some eye drops are suitable for pregnant women.
  • Treatment for giant papillary conjunctivitis
    • This condition is caused by contact lenses. This can be relieved by removing the contact lenses until symptoms are gone. The patient should also improve eye hygiene or change their lenses once the condition is treated. Anti-histamine eye drops can be used as well as mast cell stabilizer to ease the symptoms.
  • Treatment for contact conjunctivitis
    • To treat this condition, the patient should avoid the cause of the allergic reaction. If the cause is due to cosmetics, then the patient should not put anything on until the symptoms have died down. Or try an alternative to the ones you have been using. Another cause is due to eye drops. Do not use any eye drops until the doctor has prescribed one that is most suited to your condition and health. Anti-histamine and mast cell stabilizer eye drops are not able to ease the symptoms of this type of conjunctivitis.

Warning signs to watch out for:

It is very hard for doctors to differentiate infective to allergic conjunctivitis. This is particularly true on hay fever season because the eyes become red and watery. A lot of other eye condition scan cause reddening of the eyes and can be mistaken for conjunctivitis.  If just one eye is red, then it highly likely that it is caused by allergic conjunctivitis. The following symptoms should be causes of concern for the patient and should seek medical help as soon as possible:

  • The symptoms are constantly changing.
  • If there is eye pain or if the patient feels mild soreness.
  • If there are blisters or spots under or near the infected eye.
  • Vision is blurred or reduced.
  • The infected eyes have become very red.

Related Conjuctivitis articles: