What is Pink Eye?

Posted on Apr 25, 2021

Pink eye is one of the most commonly referenced eye infections, but do you know what it is?

The answer might surprise you, there really is no one definition for pink eye! Pink eye can be caused by several different things which all require different treatment methods. Getting a proper diagnosis and thus proper treatment is crucial to ensure prompt healing and prevention against worsening infection.

What is Pink Eye?

“Pink eye” is more of a blanket statement—like saying you have a sore throat—it is best to focus on different signs and symptoms, and to seek medical care from an eye doctor specifically—not an urgent care, primary care doctor, or the ER unless an eye doctor is not accessible.

Pink eye is indeed an eye infection, medically called “conjunctivitis”, but there are several different causes. The term pink eye is more of a descriptive factor as the eye literally looks pink, and sometimes even red. Therefore, a better term for pink eye would simply be an eye infection (or conjunctivitis).

Eye infections can be caused from bacteria, fungi, viruses, and sometimes even allergies. Each of these four main categories have their own treatment regimens and the treatment for one category can actually make the symptoms of another category worse!


True or False: Common Misconceptions of Pink Eye

Before we get into specifics, here are some things we regularly hear as eye doctors about pink eye—some hold some truth while others are quite false!

Pink eye is only a problem of childhood.

Answer: False! Pink eye can occur in at any age.


Pink eye is caused from someone farting in your face.

Answer: While this statement holds some truth, it is not completely correct. Fecal matter and flatulence are the body’s way of getting rid of wastes—this can include bacteria which are one of the many causes of pink eye. So could someone farting in your face cause pink eye?Yes, but it is not the typical cause.


Pink eye is very contagious.

Answer: Sometimes. Some forms of pink eye are contagious whereas others are not.


Once you have pink eye once, you’ll never get it again.

Answer: False. There is no “immunity” to pink eye. You can have it once or you can have it multiple times—although we recommend if this is a commonly recurrent issue you discuss it with your eye doctor.


My brother had pink eye a year ago and he still has some left over eyedrops. I can use those to clear up my pink eye, right?

Answer: Very false! Please do not do this, your pink eye could be very different from someone else’s, and therefore the treatment regimens are quite different.


Signs and Symptoms of Pink Eye

Since the cause of pink eye is variable, the signs and symptoms of it also vary. However, some of the most common complaints associated with pink eye include:

-Itchy Eyes

-A pink or red appearance to the eyes

Eye discharge—typically yellow, green, or white in color

-Waking up with eyes “crusted shut”

-A swollen appearance of the eyes

-Occasionally eye pain

-Occasionally reduced vision


Common Causes of Pink Eye

As briefly noted before, there are four major categories of pink eye—bacterial, viral, allergic, and fungal.

Bacterial Pink Eye

Bacterial pink eye is what is seen most frequently in children. The two most common culprits are Staph and Strep.

While Staph and Strep sound intimidating, they are actually part of the normal bacterial flora, meaning they exist naturally within the body and typically do not cause problems.

When Staph and Strep become imbalanced or travel to an area outside of their normal body organ they can cause infections like pink eye.

The reason bacterial pink eye is seen so commonly in children is due to their lifestyle. In general, children touch more things than adults—shared toys, shared school supplies, sports equipment, grass, dirt, playground equipment, etc. Children have also been known to wash their hands less frequently than adults—the combination of the two can easily result in an increase in bacteria numbers and thus lead to infections.

Bacterial pink eye has a few unique characteristics to help differentiate it from other pink eye causes. Bacterial pink eye usually affects both eyes and will produce a yellow/green discharge. The eyes may be crusted close upon awakening and you may have difficulty keeping your eyes open due to irritation and light sensitivity.

Bacterial pink eye is indeed contagious, so if you suspect your child has a bacterial eye infection it is best to keep them away from other children and call your eye doctor as soon as possible to initiate treatment and lessen the spread.

Since bacterial pink eye is contagious, it can be spread to adults, especially those who have children or work with children regularly. It is always advisable to wash hands frequently to help limit the spread of bacteria.

Bacterial pink eye is also seen frequently in contact lens wearers who might not have the best contact lens hygiene care routine.

Contact lens associated bacterial infections are serious, if you think you may have pink eye and wear contacts you should discontinue contact lens wear immediately.

Bacteria like cool, moist environments—like contact lens cases. Therefore, if you do not regularly clean your contact lens case prior to putting in the saline and contacts for overnight storage, bacteria could be lurking in the case and hence latch on to your contacts overnight.

Contact lens bacterial pink eye presents similarly to regular bacterial pink eye, however it can be more detrimental to vision as contact lens wearers are more prone to small, unnoticeable scratches (corneal abrasions) since there is something going in and out of the eye regularly.

When bacteria seep into these small abrasions and fester, it makes the eye infection much more miserable to the individual and can be more difficult to treat. Thus, contact lens wearers who have pink eye often report more pain, watery eyes, and a decrease in vision.

Bacterial eye infections are usually treated with antibiotic eye drops. In these cases, you normally want to avoid steroid eye drops, as steroids weaken the immune system to decrease inflammation and therefore result in the eyes having less of a resistance to the bacteria. Taking steroids and not antibiotics, therefore, can cause bacteria to proliferate exponentially and create a much more severe infection.


Viral Conjunctivitis and Pink Eye

Viral pink eye is more commonly seen in adults—especially in times of stress. Viral pink eye tends to be a little less concerning than bacterial, but it is still irritating and seeing your eye doctor is always a good idea.

Viral pink eye can affect only one eye or both eyes. It does not usually have discharge—if it does the color will usually be clear to mildly white.

The two most common causes of viral pink eye are adenovirus and herpes simplex virus.

Adenovirus is one of the common culprits of flu-like symptoms. If you are experiencing a sore throat, sneezing, fatigue, or other common cold symptoms, be sure to relay this information to your eye doctor.

Adenovirus pink eye is contagious for the first few weeks of the disease, but later becomes non-contagious.

Herpes Simplex related pink eye is the other major viral culprit of eye infections.

Herpes is a scary sounding diagnosis to hear, but in all actuality, it is not something to fret over. There are two subtypes of herpes simplex—type 1 is what causes cold sores and is typically the cause of Herpes simplex eye infections. The majority of the population would actually test positive for Type 1 Herpes Simplex Virus.

Type 2 is the sexually transmitted disease—just because you hear “herpes” does NOT necessarily mean you have the STD form.

Herpes viral pink eye is not typically contagious, it is mostly just annoying to the individual. It is commonly seen in times of stress—before a big exam, an important work meeting, during pregnancy, while planning a wedding, etc.

Lastly, a current area of viral pink eye research is with the COVID-19 epidemic. There has been a reported increased in pink eye cases, however there has not yet been many studies proving or disproving a connection between the two. It is definitely a topic to keep an eye on in the future.

Regardless of cause, viral eye infections tend to be self-limiting, meaning the body will take care of them on its own with due time. However, there are cases of more stubborn or severe viral pink eye in which treatment by your eye doctor will be necessary.

Viral pink eye needs to be treated with an anti-viral eye drop—antibiotics and steroids will not help in these situations. Again, steroid eye drops can actually make viral pink eye worse for the same reason it can worsen bacterial pink eye.


Allergy Related Pink Eye

Allergies are another common cause of pink eye. Allergies can be seasonal from pollen, grass, hay, etc. or can be from contact with certain materials including cosmetics, lotions, contact lens solutions, soaps, or even laundry detergent!

Allergic pink eye is not contagious whatsoever and almost always affects both eyes. It often presents with excessive watering, eye swelling, and occasionally white stringy mucous. The #1 complaint with allergic pink eye is itchiness.

If allergies are what is causing your pink eye, antibiotics and anti-virals will not help. Usually your eye doctor will prescribe an over-the-counter allergy eye drop such as Pataday or Zaditor, but sometimes this method of treatment is not enough.

Your eye doctor may recommend a prescription-grade allergy eye drop or a steroid eyedrop to help weaken the immune response and dampen inflammation (the underlying cause to your allergic pink eye).

It is also recommended if you have tried using any new cosmetics, lotions, soaps, etc. that you discontinue use in case it is the underlying agitator. If you wear contact lenses those should also be discontinued until your allergies clear up.


Fungal Pink Eye

Out of all four categories of pink eye, fungal is the most rare but also the most serious.

Fungal pink eye is commonly transmitted from contact with trees, bushes, soil, or other organic substances. For example, when doing yard work a tree branch snaps back and hits your face. You may not have any obvious cuts or injuries, but the fungus can transfer to the eye and cause a serious infection.

Unique symptoms to a fungal pink eye are pain and cloudy vision. You may have some discharge and the eye itself may appear white and cloudy instead of clear.

If you have pink eye and have been out hiking, doing yard work, swimming in a lake, or other outdoorsy activities and suspect you may have a fungal infection you need to call your eye doctor immediately as fungal infections can be permanently sight threatening.

Your eye doctor will want to get you started on an intense anti-fungal treatment program to get the situation under control as quickly as possible.


What Should I Do if I Think I Have Pink Eye?

As you can see, different causes of pink eye are treated quite differently. Without proper treatment your pink eye could get worse and even become sight threatening.

Eye doctors have many special, unique tools in office to look at your eyes and determine what the underlying cause is—therefore it is best to have your eye doctor handle your pink eye situation. When you call to make an appointment you should be prepared to answer the following questions:

-Are both eyes involved, or just one?

-When did you first notice your eye was bothering you?

-Is there any discharge? If so, what color is it? Is there a lot of discharge, or just a little bit?

-Are you in any eye pain?

-Can you still see well, or is your vision affected?

Based on your answers to these questions, your eye doctor will already have a decent idea as to what is going on. He or she will therefore determine how urgent the matter is and fit you into the schedule accordingly.

If the doctor says he or she cannot get you in until the following day or two, do not panic! Your eye doctor knows best, if it is an emergency they will find a way to fit you in ASAP. Many eye doctors even have an after-hours emergency number for eye-related problems, so always call us first!


Our eye doctors at Eye Theory in Houston, TX excel in the prescription of contact lenses, glasses and various eye diseases.  Call our optometrist at 832.831.7386 or schedule an appointment online if you would like to learn more about pink eye.  Our eye doctor, Dr. Jonathan Tsao, provides the highest quality optometry services and eye exams in the Midtown, Downtown, Museum District, Montrose, East Downtown, and Southside Commons (Southside Place) vicinities of Houston, Texas.

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