Pink eye occurs due to a bacterial or viral infection, while eye allergies are due to an allergen. Both can cause red, watery eyes.

Pink eye, or conjunctivitis, occurs due to a bacterial or viral infection and is contagious.

Eye allergies occur due to a reaction to an allergen, such as dust, pollen, or animal dander.

This article looks at the similarities and differences between the two conditions, as well as symptoms, treatment, and prevention.

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The symptoms of conjunctivitis and eye allergies can be very similar. The table below lists the symptoms of the conditions:

ConjunctivitisEye allergy
white of the eye appears red or pinkred eyes
gritty feeling in the eye or urge to rub the eyesgritty feeling in the eye or urge to rub the eyes
irritation or burning sensationeyes feel intensely itchy and may sting or burn
watery eyewatery eyes
discharge of pus or mucusmucus discharge that is white and stringy
swelling of the eyelid, the conjunctiva, or the inside of the eyelidswollen eyelids
crusting of the eyelid or eyelashes, particularly in the morning, which may stick the eye togetherusually affects both eyes
viral version often associated with recent respiratory illnesses, such as those from Haemophilus influenzae or adenovirusmay occur with other allergy symptoms, such as a runny or itchy nose and sneezing
can make contact lens wear uncomfortable, especially monthly replacement contactscan make contact lens wear uncomfortable, especially monthly replacement contacts

Identifying the possible cause of symptoms may help people distinguish whether they have pink eye or eye allergies.

Eye allergies

Symptoms may be due to an eye allergy if people have known allergies or have had recent exposure to common allergens, such as pollen.

Seasons can play a part in eye allergies. Seasonal allergies usually happen during spring or summer and occasionally in the fall. Pollen, grass, and airborne allergens can all cause eye allergies.

Eye allergies can also occur throughout the year due to allergens such as animal dander, dust, or mold spores.

With eye allergies, people may also have other symptoms of allergies, such as:

  • a runny nose
  • sneezing
  • an itchy nose

Learn more about eye allergies here.

Pink eye

Pink eye is highly contagious, and people may contract the infection from close contact with a person with pink eye. Touching the eyes with unwashed hands or using eye makeup containing the bacteria or virus may also cause pink eye.

Upper respiratory tract infections can also lead to pink eye, either from contact with another person with the infection or having the infection.

Eye allergies usually affect both eyes, whereas pink eye usually begins in one eye. Pink eye may later spread from one eye to the other.

Learn more about pink eye here.

Both pink eye and eye allergies are a form of conjunctivitis. Conjunctivitis affects the conjunctiva, which is the mucous membrane covering the front of the eye and lining the inner eyelids.

Both conditions cause:

  • redness of the eye
  • watery eyes
  • a gritty sensation in the eye as if something is in the eye

Key differences between pink eye and eye allergies include:

  • allergies usually affect both eyes, but pink eye usually starts in one eye and may then spread from one eye to the other
  • pink eye can be very contagious, while eye allergies are not
  • intense itching of the eye is usually a symptom of eye allergies rather than pink eye

Doctors can often recognize the cause of sore eyes just by looking at them. If they cannot, they may take a medical history and conduct an eye examination to check the conjunctiva and nearby tissues. A doctor may:

  • assess when symptoms began and the possible cause
  • take visual acuity measurements to check vision
  • use bright light and magnification to assess the health of the conjunctiva and eye tissues, as well as examine the inner eye structures
  • take a tear sample or a conjunctival tissue sample to test for bacterial or viral infections

Treatments for conjunctivitis aim to relieve discomfort, ease symptoms, and shorten the time of infection or inflammation.

Treatment for pink eye may include:

  • antibiotic eye drops or ointments for bacterial pink eye
  • cool compress to the eye
  • artificial tears
  • topical steroid eye drops

There is no treatment for viral conjunctivitis, but people may find cool compresses and artificial tears can help ease symptoms. Viral conjunctivitis will usually resolve by itself within 2–3 weeks.

Treatment for eye allergies may include:

Learn about eye drops for itchy eyes here.

Tips for preventing pink eye and eye allergies include:

  • washing hands frequently and always before touching the eyes
  • avoiding close contact with anyone who has pink eye
  • avoiding sharing eye makeup or eye care items
  • using a clean washcloth and towel for washing and drying the face
  • being aware of and avoiding allergy triggers wherever possible
  • washing the face after exposure to allergens, such as pollen, dust, or animal fur
  • washing clothes frequently
  • using a clean pillowcase to sleep on
  • bathing or showering before bed
  • if using contact lenses, keeping the lenses and case clean and changing contact solution daily

Pink eye and eye allergies share many similar symptoms. They may make the eye appear pink or red, feel gritty, and cause watery discharge from the eye.

Eye allergies usually affect both eyes and may link to seasonal changes or allergy triggers such as pollen, dust, or animal dander.

Pink eye is highly contagious, and people may contract a bacterial or viral infection from another person with pink eye or by touching their eye with unwashed hands.

Pink eye will resolve itself, but antibiotics may help bacterial conjunctivitis clear more quickly. Antihistamines and topical steroid eye drops may help with eye allergies.

Cool compresses and artificial tears may help with all types of conjunctivitis.