in ,

Pink eye symptoms, causes, and treatment – Conjunctivitis

Pink eye or conjunctivitis is a disease where the outer layer of the eye swells. In this article, there is its symptoms, causes, and treatment.

This article will discuss what pink eye conjunctivitis means, the different types of pink eye people can get, and how to differentiate them depending on the symptoms and other background information.

We will also be explaining if the pink eye is a serious disease and, if so, in which case it could be. Besides, answer to questions like, How is the diagnosis of this disease made, and which treatments are available for the different conjunctivitis types? Continue reading to get more information about this very common disease directly from a doctor.

What is a pink eye or conjunctivitis?

Pink eye is also known as Conjunctivitis. It is a disease in which the conjunctiva, a layer that protects the eye, becomes inflamed or irritated. This layer is a thin mucous layer that is over the eye and the inner part of the eyelid.

An infection by a bacteria, virus, parasite, or fungus can cause inflammation of the conjunctiva. Those would account for infectious conjunctivitis, but there are also noninfectious causes such as allergies or contact with toxic chemicals.

This disease is also known as pink eye as there is redness on the eye present independently of the cause. Pinkeye is one of the most common eye diseases there’s, and it affects most people at least once in their lifetime.

Primary doctors usually take care of this disease instead of eye doctors unless there are possible complications. Conjunctivitis typically only lasts for a few days or weeks. Still, an eye doctor should take care of it when it lasts longer than a month or in severe cases. 

Bacterial conjunctivitis usually associates with bacteria such as Staphylococcus aureus and Streptococcus pyogenes, which are gram-positive bacteria. The infection by these bacteria does not represent complications most of the time as the immunological system can handle them.

On the other hand, when the gram-negative bacteria cause the infection. They can lead to some complications if treatment is not applied. Some of these can be Pseudomonas, Haemophilus influenza, Moraxella, Gonorrhea, and Chlamydia.

Viral conjunctivitis, most of the time, happens because of adenovirus infection. However, there are plenty of other possibilities as common-cold viruses, the herpes virus, varicella-zoster virus (the same virus of chickenpox and shingles infection), and HIV infection. The herpes virus represents the majority of the complications of the pink eye.

What is an infectious pink eye or conjunctivitis?

Conjunctivitis depending on the type, might have different origins. On the infectious causes, there are two main ones; bacterial and viral. There are other possibilities as parasites or fungi, but they are rare and out of this article’s scope.


Bacterial conjunctivitis or bacterial pink eye is the infection of the conjunctiva by bacteria. The origin of this infection can come in several ways. People can obtain the disease by transmission from an infected person by direct contact with them or through fomite.

The latter term stands for objects where the microbe stays for some time and can infect people if brought close to the eyes. For example, towels, napkins, pillows, shirts, or a surface touched by the hands and, subsequently, the eyes.

Another common cause of bacterial pinkeye is contact lens using if the user doesn’t apply the correct hygiene. Besides, sometimes the normal bacterial flora in the conjunctiva can cause infection if there’s a change in the immunological system.


Viral conjunctivitis or viral pink eye is the infection of the conjunctiva by viruses. This is the most common cause of conjunctivitis, and, specifically, within this type, the “adenovirus” is the leading instigator of them.

It is essential to know this because some people take antibiotics to treat the viral pink eye, but it’s a viral and not bacterial infection. Antibiotics don’t treat viral infections and can result in bacterial resistance to that medication, leading to more dangerous infections.

These viruses can produce infections through fomites as previously described and also by the water in swimming pools. Viral pink eye infections are very contagious since they can spread through droplets in the air from an infected person to another.

The disease is transmittable approximately up to twelve days since the symptoms began. It can last from two to four weeks; unless the person’s immunological system has a previous problem. This differentiates it from a bacterial infection as viral ones tend to be longer.

What is an allergic pink eye or conjunctivitis?

Allergic conjunctivitis or allergic pink eye is conjunctiva inflammation due to an immunological response to an innocuous particle. Some of these can be regular dust, pollen, weeds, grass, and others. Those by themselves cannot cause an allergic response; it depends on the reaction from the person suffering.

The allergic reaction is similar to rhinitis (an allergic reaction on the nose that produces sneezing and a watery nose). There are antibodies in the mucous which catch the irritants previously mentioned and recognize them as a threat. This happens because of an error in some people’s immune systems, meaning not everybody’s antibodies react this way.

These antibodies activate a specialized type of cell; mast cells. They release inflammatory proteins, which bring other proinflammatory cells and increase blood flow to the area. This augmented blood flow and stretched blood vessels cause the characteristic eye redness of the disease.

Five subtypes of allergic conjunctivitis

  • Perennial allergic conjunctivitis
  • Seasonal allergic conjunctivitis
  • Atopic keratoconjunctivitis
  • Vernal keratoconjunctivitis
  • Giant papillary conjunctivitis. 

Perennial allergic conjunctivitis and seasonal allergic conjunctivitis are quite similar in most aspects. The only significant difference is that the cause of seasonal pinkeye is because of particular irritants of each season. For example, in the summertime, the pollen from grass is the leading cause of seasonal conjunctivitis.

In autumn, the pollen from weeds is the leading cause, and in the spring, the pollen from trees. The time the person suffers from the allergic reaction will depend on which of these they are allergic to. Sometimes people can be susceptible to multiple of these particles, making it a bigger of a problem. There is swelling in perennial allergic conjunctivitis due to irritants independent of any season, like dust inside a home or dog hair.

Which are the sign and symptoms of viral pinkeye?

Conjunctivitis, due to viral infection, has a set of characteristics of its own as well as other general ones.

The common symptoms a person presents are:

  • Itchiness of the eyes
  • Eye redness
  • Watery eyes
  • The feeling of a foreign object stuck between the eye and the eyelid
  • Eye discharge
  • Eyelids sticking to each other in the morning (Glued eyes)
  • Feeling bothered by the light
Pink eye

Usually, people have been in contact with someone with a pink eye at workplaces or in their own homes. There is also a relation with having symptoms of a common cold like a sore throat and fatigue previous days or simultaneously.

The infection by adenovirus typically presents like that and can be on one eye, although most times happen in both. A sign professionals observe is the presence of inflamed ganglia near the ears, something predominant of viral infections.

Viral conjunctivitis can be due to several viruses, and they can be different from the typical pinkeye adenovirus infection. Eye herpes virus infection commonly affects children and is quite similar to adenovirus, except it presents vesicles on eyelids. These are blisters, small lesions with a clear liquid in the center of it.

The varicella-zoster infection comes with a fever, malaise, and vesicles and only happens in one eye. Sometimes infection of vesicles can occur if they are not adequately managed, causing them to become pustules. This latter lesion is a type similar to vesicles but has pus inside of it.

Which are the sign and symptoms of bacterial pink eye or conjunctivitis?

The sign and symptoms of bacterial conjunctivitis can be very similar to those of a viral conjunctivitis infection. Instead of watery eyes, there is a more purulent discharge that comes from the eyes.

File:Swollen eye with conjunctivitis.jpg
Swollen eye with conjunctivitis

They can have yellow, green, or white coloration depending on the microbe causing the infection. The stickiness between eyelids in the mornings is more prominent than in a viral infection. This can be up to the point of not being able to open their eyes without assistance or water use.

The appearance of inflamed ganglia near the ears is not common on the bacterial pink eye, except on infections by gonorrhea. This is a sexually transmitted disease, just like chlamydia, which is why it’s essential to know the sexual history of the patient. With this type of bacteria, the purulent secretions are more conspicuous than by other bacteria.

How allergic pink eye looks like?

Allergic conjunctivitis, in general, has various symptoms similar to viral or bacterial pinkeye. The most crucial symptom in allergies, in general, is itchiness.

If there is no itching, doctors would even suspect the first of a bacteria or a viral infection. The red-eye is quite a prominent symptom here, not only because of the dilatation of blood vessels. This also happens because of the constant rubbing of the eyes, leading to small blood vessels to break.

In the patients who suffer from allergic conjunctivitis, there is an association with asthma, rhinitis, and dermatitis. These diseases are due to allergies, a hypersensitivity of the immunological system to generally innocuous particles.

In asthma, the upper airways’ muscles get smaller, and other cells produce mucous, making the airways smaller. This shows the importance of knowing the presence of allergies since some of them can be life-threatening. Another symptom in an allergic pink eye is eye pain due to the eyes’ rubbing and irritation.

How serious is the pink eye?

Pink eye is not a disease that frequently presents any complications. Some types of these can go on without any treatment and disappear; meanwhile, others need some topic or oral treatment.

Some patients with an allergic pink eye can have eye scarring due to eye rubbing or even develop later on infectious pinkeye. Meanwhile, in patients with a viral infection, it usually resolves itself. For example, if it is due to adenovirus.

However, when it is because of a virus-like herpes simplex or varicella-zoster (the same as herpes zoster or shingles disease), the infection could have vesicles within the skin. Besides, a disease like herpes zoster or shingles is associated with nerve damage that can lead to pain in the upper face area.

The bacterial pink eye generally needs treatment, although, without it, complications are not common either. Yet, in some cases, like gonorrhea infections, it is a medical emergency that requires immediate assessment and treatment. The infection can cause ulcers in the eye if the infection goes past the conjunctiva. This might mean some visual loss level depending on how severe it’s or if the doctor applies treatment on time. 

Complications in newborns.

In newborns, there is a form of the disease doctors call neonatal conjunctivitis. In this disease, the child’s eye suffers from an infection in the conjunctiva, similar to adults’ experience.

The eye infection in newborns can lead to severe life-threatening consequences if a doctor does not treat it. Some of them can be meningitis, which is the infection of the layers that protect the brain. Also, It can cause pneumonia, which is the infection of the lower airways.

The mother can transmit a bacterium like gonorrhea or chlamydia through the birth canal when giving birth, causing the disease. This is why testing for sexually transmitted diseases in pregnant women is crucial, as something so simple can lead to death. Also, a blocked tear duct is common in newborns and can cause neonatal conjunctivitis.

How do you know you have this disease?

Conjunctivitis is a disease that doctors can diagnose easily without the need for any particular laboratory test. Usually, pink eye symptoms such as eye redness, itching, and watery eyes are enough to identify the disease.

The clinical history is also essential when assessing the patient since it varies depending on the type of pinkeye. If the patient who has the illness was in contact with someone with a pink eye, they probably got infected.

Sometimes people don’t know they were in contact with someone with the disease. This makes it crucial to ask the correct questions and determine if anyone in their surroundings had pinkeye symptoms.

Besides, suppose the patient suffers from asthma, rhinitis, or dermatitis. In that case, it can indicate whether the conjunctivitis is allergic or it isn’t. The season and the place where they live give more information about if the allergy is seasonal or perennial. This is important to know to prevent future allergic conjunctivitis, rhinitis, and even asthma, a life-threatening condition.

A procedure that doctors sometimes make is conjunctival scrapping. It consists of swabbing the fluid or secretion of the eyelid for then to make a culture. This entails putting this secretion in a laboratory setting for it to grow.

Specialists evaluate this growth and determine what kind of bacteria is present and what medication is more suitable. Imaging studies do not add anything to the diagnosis as they are ineffective in this type of disease.

A hematologic test may show some differences depending on whether the infection is viral, bacterial, or allergic. There are tests for an allergic pink eye that determines if a person has allergies of any type. This can be quite general and nonspecific but can lead the way to a diagnosis.

Is conjunctivitis treatable? Will Benadryl help pink eye?

For each cause of conjunctivitis, the approach will be different. Not everything works for each type.


In a bacterial pink eye, antibiotic treatment cures the affected eye. The purpose of the antibiotic is to reduce the infection time and decrease the disease’s spread. This treatment comes in the form of antibiotic eye drops or antibiotic ointment. The patient has to apply them directly to the infected eye regularly to make sure the disease cures correctly.

Sometimes the antibiotic ointment or the antibiotic drop can cause dry eye. Doctors typically recommend artificial tears to help lubricate the conjunctiva and the eyeball itself.


For viral infections, there is no standard medication that professionals can recommend to cure the disease. Antibiotics do not work against viral infections as they only work against bacteria, which are a different type of microbes. To treat symptoms, patients can use a cold compress and artificial tears, which increases relief.

Sadly, the treatment for adenovirus infections only aims to reduce the bothering symptoms. However, for not so common viral infections like varicella-zoster or herpes simplex, patients can use antiviral medication. These can be topical or oral, depending on each disease.


In allergic conjunctivitis, the standard treatment is an allergy medication. These can be topical or oral, depending on the person’s needs.

Topical allergy medication doesn’t last as long as a systemic orally taken medicine, but the latter has side effects. Systemic medication can produce drowsiness and a dry mouth, but it has a more long-lasting effect.

An example of an allergy medication would be Benadryl, meaning it can only help with an allergic pink eye. Artificial tears are necessary and thin, the possible irritant agent on the eyes protecting the conjunctiva. Other medications like steroids and no steroid anti-inflammatory treatment are not as effective, but patients can use them as well.

Do you have symptoms of this disease?

This is a Pink Eye Symptoms Checker. It gathers the most important signs, symptoms, and risk factors for this disease. Therefore, it would tell anybody who uses it the likelihood of their symptoms because of the pink eye. It is free and would only take a few minutes to complete.

What do you think?

Written by Dr. Esteban Kosak

Doctor of Medicine - MD Recently Graduated from Medical School and inspired to aid the global population during this situation. I think that we shall no longer be waiting to see a doctor when we feel sick. Several times we feel disease searches in Google drive us to a rabbit hole and come out thinking that we may die of cancer or something very serious, given that symptoms may seem to fit a wide variety of illnesses. Since I recently graduated from medical school. I have all the medical information fresh in my mind. My thorough experience as an expert researcher allows me to very-well known the different diseases and conditions that affect human bodies. Empowered by the United Nations 17 Sustainable Development Goals (SGDs). I think that we all can provide a grain of sand to help humanity. That's why we created Symptoms.Care a place where you can come and screen your symptoms and find what different illnesses can be related to them. Armed with the right information you can instantly, discretely, secure and from the comfort of your home talk with a Doctor that can Evaluate your Symptoms and help you seek the right treatment.


Leave a Reply

Your email address will not be published. Required fields are marked *



Eye discharge? Let us check it – Pink Eye Symptoms Checker

Meniere disease symptoms, causes, and treatment – Meniere’s disease