Red eyes are one of the most frequent eye-related reasons for a visit to a doctor. This is not a disease – merely a symptom of an inflammation. While it might be difficult even for an experienced physician to set the diagnosis right from the first time, there are couple of pointers you can find helpful in investigating the cause of the red eye.
When do you know that red eye is an infection?
Only one eye is red (unless there are other infection signs)
There is also fever or other signs of infection
There was a contact with many children (kindergarten, school etc)
You got a report from school that someone has Pink Eye
No previous allergies
No new exposures to pets
It is not an allergy season
Allergy is not exactly a disease – it happens when the body is exposed to a protein and mistakenly attacks it as intruder upon contact. So, many allergy signs can be absolutely the same as infection. Yet, here are allergy giveaway:
Allergic symptoms in the eyes already happened before
Other organs are involved – sneezing, congested or runny nose, asthma
There was a direct contact with the pet or allergy season just started
Both eyes are itchy and red
There is no fever or other signs of infection, no sick contacts
What Are the Symptoms of Allergic Eye?
Symptoms of the allergic eye are slightly different from eye infection:
Usually both eyes are affected equally
Redness of the eyelids and conjunctiva
Sometimes there is rash on the eyelids
Swelling of the eyelids, sometimes leaving very small space in between
Thick whitish streaks of mucus in the eye and on the eyelids. This discharge can glue the eyelids together covering eyelids, so it is difficult to open the eyes in the morning
Intense eye itching and rubbing
Children do not show the signs of distress (as with infection), but in general can become itchy and sneezy. Kids who have asthma may have wheezing and cough. If this is a reaction to the seasonal allergy that continues for a while, there is also significant fatigue, attention deficit, irritability and falling grade for children in school.
In a situation of the systemic allergic reaction (anaphylaxis) eyes might be the first place showing the problem. Frequently first reaction is red eyes and swelling of the eyelids with hives (mosquito bite – type of reaction). This is a well-known sign of the food allergy as well as environmental. If red swollen eyes appear in a child who just ate a shrimp or a peanut – this is an emergency and must be immediately treated with epi-pen!
Meanwhile, many parents know well that a close contact with a cat or rolling in the grass are notorious to causing their children’s red eyes and itch.
What Are the Symptoms of Pink Eye?
Here are the symptoms of eye infection:
Usually, symptoms are in one eye only (for a bacterial conjunctivitis)
Both eyes are involved as a part of systemic infection, such as adenovirus or flu
Problem starts abruptly from a feeling of ‘sand in the eye’
Withing hours symptoms progress to significant pain in the eye
Itching might be present, but not always
Eye becomes very red (conjunctiva inflammation)
The yellowish or green pus-looking discharge accumulates in the eye and spreads on the eyelid and eyelashes
Photosensitivity to light is significant
Systemic signs are common, especially in a viral infection
Most of the time a headache or malaise is present at the same time as eye symptoms started. Pink eye is very contagious, so other children in the family or their parents might start having the same symptoms very soon.
Pink eye usually is not coming back, at least for a while. If symptoms tend to occur repeatedly after petting a cat, or during spring outside of the house, you must explore the allergy as the reason for a red eye. as we discussed above, the infection and allergy mascaraed each other. In children even a fever can be elevated when allergic symptoms start.
What causes Allergic Eye?
It is unfortunate, but actually the normal proteins in our environment are the cause of the allergic eye symptoms. The actual trigger of the symptoms can be one or multiple. And they do accumulate overtime. Even if the first symptoms were because of the kitten, then the same symptoms can be caused by the tree pollen or dust mites.
What causes Pink Eye?
Pink eye is an infection. So, the infection of the eye can be caused by:
Rubeola (measles) virus
Herpesviruses, including. Herpes simplex virus
Picornaviruses, such as coxsackievirus A24 and enterovirus 70 (which has caused outbreaks in other countries)
How is Allergic vs Pink Eye diagnosed?
First of all, if the symptoms are significant or don’t go away in a few days – go see a doctor. You can start in the primary care clinic. Most doctors and nurse practitioner know this symptom very well, and can diagnose it without any other tests. Treating red eyes with prescription medicines is almost a test – an antibiotic eye drops will immediately stop an infection, while antihistamines will stop allergic reaction. What if the red eye symptoms do not go away within a week, or even getting worse? This is the time to see a specialist. Where do you go? Well, if all the clues are for the allergy – you need to schedule an appointment with an allergy clinic.
Here you will have test to diagnose eye allergy:
Questionnaire of exposures and family history
Skin test for allergens (a test for environmental allergens and food allergens will tell you what caused the problem in 30 minutes!)
Patch test for chemicals (if a contact allergy is a problem, a test for the contact sensitivity can be done)
Blood test for the allergy panel can be ordered if the skin test not possible
Now, what if all allergy tests are negative? This is very useful, as the doctor knows now that the allergy is not an answer. The other tests that check your immunity and other systemic issues are in order:
Blood tests for autoimmune and genetic diseases
Infectious diseases panel to check for parasites and chronic infections
Blood test for vitamin and mineral deficiency
You will be also recommended to see an optometrist or ophthalmologist to see if there is an eye disease that is causing a problem.
An eye doctor has many specific tests to diagnose the eye condition:
Slit lamp exam (looking for an eye scratch, ulcer or foreign body)
Intraocular pressure (IOP) measurement (to rule out glaucoma)
Retina exam with electronic microscope systems (this can find the eye parasites or changes of the retina with autoimmune diseases)
How Is Allergic or Pink Eye Treated?
As we discussed above, the treatment for allergy is very different from infection.
Ocular (topical) decongestants. These drops do not treat, but help reduce the eye redness by constricting the capillary of the conjunctiva. While very effective for a few hours, these drops cause a rebound effect – blood vessels over-dilate when medicine stops working. Just like nose decongestants, this type of medicine is addictive because of their mode of action. It is available over the counter, so be careful not to get in more trouble with red eyes that keep coming back.
Ocular (topical) antihistamines. Histamine blocking eye drops can be prescribed by your doctor. They are slightly helpful with infection, but work very well for eye allergy. While most need to be applied 3-4 times a day, there are also eye drops that have prolonged action and can be used once a day. The treatment component does not cause any side effects or addiction, but the generic drops frequently use cheap ingredients that can cause worsening of the problem and significant burning when applied.
Ocular (topical) lubricants. Artificial tears are available over the counter and can be uses as needed. They will not help at all for the infection, but can help reduce the redness and irritation in a dry eye syndrome. They are sometimes prescribed for people who wear contact lens to reduce uncomfortable feeling.
Ocular (topical) steroids. This is one of the medications that needs to be taken seriously. Even in a small dose these meds can cause side effects such as cataract or increased intraocular pressure. They should not be used for a pink eye in children and true allergy. The autoimmune inflammation and contact reaction are the main reasons to use ocular steroids.
Ocular (topical) mast cell stabilizers (such as Cromolyn). This medicine makes mast cells (which carry histamine) less reactive, so they do not respond to allergens. The action is short, and they need to be applied every few hours to work well. At the same time they do not have side effects, so can be used safely to control symptoms while you work on allergy prevention.
Systemic (oral) versions of the above medications. These should not be used frequently. Only severe situations need oral medications.
Immunotherapy. If the allergy is not affecting the lifestyle and can be controlled just with the house cleaning or pet care, there is no need for immunotherapy. This treatment should be considered for everyone whose symptoms are bad or prolonged. Immunotherapy such as shots or sublingual drops is a serious undertaking due to cost and timing, but it is a natural way to get rid of allergy and is medication-free. Your allergist can help you decide what is the best option for you.
How Can I Relieve Symptoms of Allergic Pink Eye?
Before you go to the doctor there are few simple things you can try to stop symptoms of the allergic pink eye:
Wash your face with cold or lukewarm water. Pay a special attention to the eyelids – do not squint, wash the skin from the nose-out, do not rub. Simple splashing of the eyes may wash off the allergen
Do not rub the eyes after petting a cat or a dog – wash your hands first
Use black tea compress
Clean up the house from dust and dander, make sure it is well-ventilated
Run a HEPA air filter – make sure its filter is rated to eliminate all allergens
Eliminate as much dust mites as possible. Read the medical guide on how to do that – it is not an easy adventure and can be pricy if you do not discuss essentials with an allergist. Not all measures are necessary or effective for allergy relief.
Other Tips for Allergic Pink Eye
Allergy is a common problem nowadays. Even babies can develop allergic eye symptoms within first months of life. While many measures can help reduce symptoms, you need to remember that is the condition is caused by abnormal immune reaction. It is best to stop allergy all together by finding what exactly caused it instead of using multiple medications daily to cover the symptoms.
Immune system is the main reason someone develops allergy. Immunity needs to be neutral – our body needs to tolerate (not attack) all proteins surrounding us. If it is agitated, immune cells go into a “war” with normal surrounding – this overuses energy and resources and predisposes our body to infections, cancer and autoimmune illness. Here are tips on preventing allergy (and allergic eye reactions):
Keep your house chemical-free. Use baking soda and vinegar for cleaning, use natural soaps and shampoos
Do not use antibacterial soaps – they kill natural protective bacteria on the skin that is important for normal immune balance
Avoid exposure to agricultural chemicals – pesticides, herbicides, growth factors and genetically modified proteins
If your immune system is healthy it will serve you well and protect from infections and cancers.
When to see a doctor
All normal infections should resolve within a week. If the problem persisted longer or keep coming back – time to see a doctor. Well, we kind of know when to go to the urgent care – acute pain, bleeding or general symptoms of concern (headache, loss of consciousness, trauma etc.). It is better to be safe then sorry when it comes to the eyes – anything that causes a significant concern is a reason for check-up with a primary care clinic, anything more serious that does not go away is a reason for a consultation with a specialist.