The Call-On-Doc Guide to Pink Eye

The conjunctiva is a clear, thin membrane that covers the front surface of the eye and lines the inside of the eyelids. It plays a crucial role in protecting the eye, maintaining its health, and also how pink eye spreads. More specifically, when a bacteria or virus comes into contact with the eye, it multiplies and activates the body’s immune response. This, in turn, results in the blood vessels swelling and making the eye red, causing tears and eye drainage that can spread the condition. (2)

Additionally, the infection doesn’t necessarily need a virus or bacteria to be present in the eye. Often referred to as non-infectious conjunctivitis, this variation of pink eye is non-contagious and is caused by allergens, irritants, foreign bodies, chemical exposure, and environmental factors. Instead of a virus or bacteria initiating the body’s immune response, the conjunctiva does so after being irritated and produces a similar response. (3)

• Allergens: Allergens trigger pink eye, known as allergic conjunctivitis, by initiating an immune response in the conjunctiva. When allergens like pollen, pet dander, or dust mites come into contact with the eye, the immune system releases chemicals such as histamines. 
• Bacteria: Bacterial pink eye, or bacterial conjunctivitis, occurs when harmful bacteria, such as Staphylococcus aureus or Streptococcus pneumoniae, come into contact with the conjunctiva. These bacteria can rapidly multiply on the conjunctival surface, releasing toxins and triggering an immune response. 
• Chemicals: Chemicals can induce pink eye, or chemical conjunctivitis, by irritating and inflaming the conjunctiva. Direct exposure to irritating substances like household cleaning agents, industrial chemicals, or noxious fumes can lead to an immediate inflammatory response in the conjunctiva.
• Contact Lenses: Contact lenses can contribute to pink eye, or contact lens-related conjunctivitis, due to improper hygiene, overuse, or allergic reactions. When contact lenses are not properly cleaned, disinfected, or stored, harmful microorganisms or debris can accumulate on the lens surface. Extended wear of contact lenses can lead to reduced oxygen supply to the cornea and conjunctiva, making them more susceptible to infections. Additionally, some individuals may develop an allergic response to the lens material or the solutions used, leading to allergic conjunctivitis. 
• Foreign Bodies: Foreign bodies, such as particles of dust, debris, or small objects, can trigger pink eye, known as mechanical conjunctivitis, when they come into contact with the conjunctiva. The foreign object can physically irritate the delicate surface of the conjunctiva, leading to an immediate inflammatory response.
• Fungi: Fungal pink eye, or fungal conjunctivitis, arises when fungal microorganisms come into contact with the conjunctiva. Fungi can infiltrate the conjunctiva and proliferate, inciting an immune response. Depending on the type of fungus involved, symptoms can vary but should be attended to by a medical professional immediately. 
• Parasites and Viruses: Parasites can induce pink eye, or conjunctivitis, by infesting the conjunctiva. When parasites, such as lice or mites, make contact with the eye area, they can embed themselves in the conjunctiva or its surrounding tissues. This intrusion prompts an inflammatory response from the immune system, leading to redness, swelling, and irritation that characterizes pink eye. The presence of parasites can cause itching, discomfort, and a sensation of foreign bodies in the eye. 
• Pollutants: Pollutants can contribute to pink eye, or environmental conjunctivitis, by exposing the conjunctiva to harmful particles. These pollutants, which can include smoke, smog, dust, and other airborne irritants, can directly irritate and inflame the conjunctiva upon contact. 

Pink eye symptoms, or conjunctivitis, can vary based on the underlying cause (infectious, allergic, irritative, etc.), but common symptoms may include:

• Redness: The blood vessels in the conjunctiva become dilated and more visible, leading to the characteristic red or pink appearance of the eye. The severity of redness can vary, ranging from mild to intense.
• Irritation: The eyes may feel itchy, scratchy, or like there's a persistent foreign object present, prompting the urge to rub or scratch them, which can worsen the irritation.
• Watery Discharge: The eyes may produce an excessive amount of tears as a response to irritation. These tears can appear clear and watery or become thicker and more sticky over time, causing the eyelids to stick together, especially after sleep.
• Swelling: Inflammation of the conjunctiva can lead to swelling or puffiness around the eyes, making them look swollen and potentially affecting comfort and vision.
• Burning or Stinging: The eyes may experience a burning or stinging sensation due to inflammation and irritation of the sensitive conjunctival tissues.
• Foreign Body Sensation: People with pink eye may feel as though there's a foreign object, like sand or grit, in their eye, which can be uncomfortable and irritating.
• Light Sensitivity: Photophobia, or sensitivity to light, is a common symptom of conjunctivitis. Bright lights can exacerbate discomfort and cause squinting.
• Blurry Vision: Excessive tearing, discharge, or inflammation can temporarily blur vision. This can affect the clarity of vision and make activities like reading or driving challenging.
• Crusting: After periods of sleep, discharge from the eyes can dry and harden, causing the eyelids to stick together and leading to crusting around the eyelashes. Gently cleaning the area can help alleviate this symptom.
• Tearing: As a reaction to irritation, the eyes may produce more tears than usual. This can contribute to watery discharge and blurred vision.
• Eye Pain: Some individuals with conjunctivitis may experience mild to moderate eye discomfort or pain, especially if the eyes are rubbed excessively.
• Swollen Lymph Nodes: Viral conjunctivitis can sometimes lead to swollen lymph nodes located near the ears, reflecting the body's immune response to the infection.

The duration of pink eye symptoms and the condition itself can vary based on the underlying cause and the type of conjunctivitis. Here's a general overview:

• Viral Conjunctivitis: Viral pink eye caused by viruses like adenoviruses is highly contagious and can last for about 1 to 3 weeks. It often starts in one eye and may spread to the other. Symptoms can be more severe in the first few days and gradually improve over time.
• Bacterial Conjunctivitis: Bacterial pink eye caused by bacteria like Staphylococcus aureus or Streptococcus pneumoniae can be treated with antibiotics. Symptoms often improve within a few days of starting treatment, but it's important to complete the full course of antibiotics to prevent recurrence.
• Allergic Conjunctivitis: Allergic pink eye triggered by allergens like pollen or pet dander can last as long as the allergen exposure continues. This could be seasonal (e.g., pollen) or ongoing (e.g., pet allergies).
• Irritative Conjunctivitis: If the conjunctivitis is caused by irritants like chemicals or foreign objects, symptoms can resolve once the irritant is removed and the eyes have had time to heal, usually within a few days.
• Mechanical Conjunctivitis: Mechanical pink eye caused by physical irritation or injury, such as foreign bodies, may improve relatively quickly after the irritant is removed, but complete healing can take a few days.
• Environmental Conjunctivitis: Conjunctivitis caused by environmental factors like pollutants or dry air can persist as long as the exposure continues. Symptoms may improve once the eyes are no longer exposed to the triggering conditions.

For medical providers, pink eye is easy to diagnose through a discussion about medical history, a physical examination, and potential tests (if needed). The primary part of the process surrounds the discussion and visual confirmation of pink eye symptoms most commonly seen. During the physical examination, the doctor carefully inspects the eyes for signs of redness, swelling, discharge, and other characteristic features. (5) As is the case with CallonDoc, this does not necessarily need to be done in person, as photos taken with the patient’s phone will suffice. 

• Allergic Reactions: Allergic reactions, such as seasonal allergies or reactions to cosmetics, can lead to redness, itching, and watery eyes similar to pink eye.
• Dry Eye Syndrome: Dry eyes can cause redness, irritation, and a foreign body sensation, which may mimic the symptoms of pink eye.
• Corneal Abrasions: Scratches on the cornea can lead to redness, pain, and discomfort, similar to pink eye.
• Uveitis: Uveitis is inflammation of the uvea, the middle layer of the eye. It can lead to redness, pain, and sensitivity to light.
• Blepharitis: Inflammation of the eyelid margins, known as blepharitis, can cause red and swollen eyelids, which might be confused with pink eye.
• Conjunctival Hemorrhage: A burst blood vessel in the eye can cause a bright red patch on the white of the eye, resembling pink eye.
• Viral or Bacterial Infections: Conditions like herpes simplex keratitis (an infection of the cornea) or styes (bacterial infections of the eyelid glands) can have symptoms similar to conjunctivitis.

Pink eye (conjunctivitis) and styes are two distinct eye conditions, but they can share some similarities and occasionally occur together.

• Pink Eye (Conjunctivitis): Pink eye refers to inflammation of the conjunctiva, the thin tissue that covers the front of the eye and lines the inner eyelids. It can be caused by infections (viral or bacterial), allergies, irritants, or environmental factors. Pink eye leads to symptoms such as redness, irritation, watery or sticky discharge, and a gritty feeling in the eyes.
• Stye (Hordeolum): A stye is a painful, red lump that develops on the eyelid. It is typically caused by a bacterial infection of an eyelid gland, often due to the Staphylococcus bacteria. Styes can occur externally (external stye) at the base of an eyelash or internally (internal stye) on the inner surface of the eyelid. Symptoms include a localized, tender bump, redness, swelling, and potential discomfort.

While pink eye and stye have different causes and primary locations, they can sometimes be related in the sense that both involve inflammation of the eye or eyelid tissues. Additionally, some of the symptoms, such as redness and discomfort, can overlap between the two conditions.

Viral Pink Eye:

• Onset: Viral pink eye often develops more gradually over a few days.
• Symptoms: Watery discharge is common in viral conjunctivitis, and discharge may be clear or slightly thick.
• Contagiousness: Viral conjunctivitis is highly contagious, especially in the first week. It can spread through direct contact, respiratory droplets, or touching contaminated surfaces.
• Associated Symptoms: Viral pink eye may be accompanied by cold-like symptoms such as sneezing, runny nose, or sore throat.

Bacterial Pink Eye:

• Onset: Bacterial pink eye can develop suddenly and progress rapidly.
• Symptoms: Bacterial conjunctivitis often has a thicker, yellow or green discharge that can cause eyelids to stick together.
• Contagiousness: Bacterial conjunctivitis is contagious but is usually less contagious than viral conjunctivitis.
• Associated Symptoms: Bacterial pink eye might be associated with a feeling of grittiness or irritation, and there might be more discomfort or mild pain.

The treatment for pink eye (conjunctivitis) depends on the underlying cause, whether it's viral, bacterial, allergic, or due to irritants. For that reason, it’s important to consult a medical provider when pink eye symptoms grow worse in severity or lasts longer than a week. Prior to seeking medical assistance, here are some general measures that can help alleviate symptoms and promote faster recovery:

• Hygiene and Cleanliness: Wash your hands frequently with soap and water, avoid touching your eyes, and avoid sharing towels or personal items to prevent the spread of infection.
• Warm Compresses: Applying warm compresses to the eyes can help relieve discomfort and reduce crusting, especially in cases of bacterial or viral conjunctivitis.
• Eye Drops: Lubricating eye drops or artificial tears can help soothe irritation and keep the eyes moisturized.
• Allergy Medications: For allergic conjunctivitis, antihistamines or allergy eye drops can help alleviate symptoms.
• Avoiding Allergens or Irritants: If your pink eye is due to allergens or irritants, avoiding the trigger can help prevent and reduce symptoms.
• Proper Contact Lens Care: If you wear contact lenses, follow proper hygiene, remove them when necessary, and avoid wearing them until symptoms improve.
• Rest and Hydration: Getting adequate sleep and staying well-hydrated can support overall eye health and immune function.

Antibiotics are not necessarily needed in most cases aside from those of bacterial conjunctivitis. The most common treatment options CallonDoc offers can include: 

• Erythromycin ointment: effectively treats bacterial pink eye by targeting and inhibiting the growth of bacteria responsible for the infection. As a macrolide antibiotic, erythromycin interferes with the bacteria's ability to synthesize essential proteins required for their reproduction and survival. When applied topically to the affected eye, the ointment directly combats the bacterial presence on the conjunctiva, gradually reducing their numbers. 
• Moxifloxacin drops: Moxifloxacin eye drops effectively treat bacterial pink eye by directly targeting the underlying bacterial infection and inhibiting its growth. Moxifloxacin belongs to the fluoroquinolone class of antibiotics and works by interfering with the bacterial DNA replication process, preventing bacteria from reproducing and spreading. When instilled into the affected eye, moxifloxacin eye drops directly combat the bacteria on the conjunctiva, reducing their numbers and curbing the infection. 
• Ofloxacin drops: Ofloxacin eye drops effectively treat bacterial pink eye (bacterial conjunctivitis) by directly targeting and eradicating the underlying bacterial infection. Ofloxacin is a fluoroquinolone antibiotic that works by inhibiting the bacterial DNA replication process, preventing the bacteria from multiplying and spreading. When applied to the affected eye, Ofloxacin eye drops act locally to combat the bacterial presence on the conjunctiva, gradually reducing their numbers. 

When applied to the infected eyes, each prescription works to target pink eye symptoms like redness, discharge, and discomfort before alleviating them shortly after application. 

In many cases, pink eye symptoms will be reduced on their own within several days that, after resting, hydrating, and use of over-the-counter medication. However, medical professionals insist upon seeking out a consultation to prevent lasting damage from the infection or to stop it from spreading to others.

In cases of bacterial or viral conjunctivitis, it's advisable to stay home until you've been on appropriate treatment for at least 24 hours to prevent spreading the infection to others. Viral conjunctivitis, in particular, can be highly contagious in its initial stages. If your pink eye is caused by allergens or irritants, staying home may not be necessary unless your discomfort is severe. However, if your symptoms are disruptive, itchy, or affecting your vision, it's a good idea to rest and seek medical advice. (6)

• Hand Hygiene: Wash your hands frequently with soap and water, especially after touching your face, eyes, or objects that might be contaminated.
• Avoid Touching Eyes: Refrain from touching your eyes with unwashed hands to reduce the risk of introducing germs.
• Avoid Sharing Personal Items: Do not share items like towels, pillowcases, cosmetics, or contact lenses with others, as these can spread germs that cause pink eye.
• Practice Good Contact Lens Hygiene: If you wear contact lenses, follow proper hygiene guidelines, such as washing hands before handling lenses, using proper cleaning solutions, and replacing lenses as recommended.
• Protective Eyewear: Use protective eyewear, such as goggles, when swimming in pools or engaging in activities where exposure to irritants or contaminants is possible.
• Allergen Avoidance: If you have allergies that trigger pink eye, such as pollen or pet dander, try to avoid allergens or use appropriate measures to minimize exposure.
• Good Respiratory Hygiene: Cover your mouth and nose when coughing or sneezing to prevent respiratory droplets from coming into contact with your eyes.
• Regular Eye Care: Maintain good eye health and hygiene by not rubbing your eyes excessively and cleaning your eyelids with mild soap and water as needed.
• Avoid Close Contact: If you have pink eye or are around someone who does, avoid close contact and follow proper hygiene to prevent spreading the infection.
• Proper Cleaning: Clean and disinfect frequently touched surfaces in your living environment, especially if someone in your household has pink eye.

While these measures can help reduce the risk of pink eye, it's important to remember that some cases are unavoidable. If you suspect you have pink eye or develop symptoms, healthcare providers like CallonDoc make it easy to get diagnosed and treated the same day!

1. Yeung, Karen K., and Andrew A. Dahl. “Bacterial Conjunctivitis (Pink Eye): Practice Essentials, Background, Pathophysiology.” Medscape Reference, 7 February 2023, https://emedicine.medscape.com/article/1191730-overview.
2. “Pink Eye (Conjunctivitis): Causes, Treatment & Prevention.” Cleveland Clinic, 22 August 2022, https://my.clevelandclinic.org/health/diseases/pink-eye-conjunctivitis. 
3. Azari, Amir A, and Neal P Barney. “Conjunctivitis: a systematic review of diagnosis and treatment.” JAMA vol. 310,16 (2013): 1721-9, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4049531/. 
4. “Signs and Symptoms of Pink Eye (Conjunctivitis).” CDC, https://www.cdc.gov/conjunctivitis/signs-symptoms/index.html.
5. “Diagnosing Pink Eye (Conjunctivitis).” CDC, https://www.cdc.gov/conjunctivitis/index.html.
6. “How Pink Eye (Conjunctivitis) Spreads.” CDC, https://www.cdc.gov/conjunctivitis/causes/index.html.