How quickly symptoms of pink eye develop depends on the cause. Allergic pink eye may develop suddenly. Bacterial or viral pink eye can take 12 hours to 12 days for symptoms to appear.

Pink eye (conjunctivitis) is a common type of eye infection that results from inflammation of the conjunctiva. The conjunctiva is the transparent film, or membrane, that covers your eyeball and lines the inside of your eyelid.

Pink eye could be because of:

  • viruses such as adenoviruses, herpes simplex, and measles (rubeola)
  • bacteria such as Streptococcus
  • allergies such as pollen or chemicals

In babies, pink eye sometimes results from being born with blocked tear ducts that don’t completely open. Babies may also get a serious form of pink eye from bacteria that reside within the birth canal. Clinicians often give babies antibacterial eye drops shortly after birth to avoid this and other bacterial infections.

How quickly pink eye develops is usually dependent on the cause. In this article, we’ll look at what factors may cause pink eye to develop suddenly, what early symptoms to look for, and when to look for medical help.

Who’s at risk of pink eye?

Anyone can get pink eye, but some people are more at risk. These include:

  • children under 5 years old
  • people who work or commute in close conditions
  • people who live, spend time, or work in group settings such as schools or nursing homes
  • people who wear contact lenses

The viruses and bacteria that cause conjunctivitis are very contagious. These pathogens spread quickly and easily through:

  • close personal contact
  • airborne droplets from coughs and sneezes
  • touching contaminated surfaces

How quickly symptoms start will depend on the source of the infection.

Type of conjunctivitisTime to onset of symptoms
Bacterial24–72 hours
Viral12 hours–12 days
AllergicOnset of symptoms may occur immediately upon contact

It’s not uncommon to go to sleep with no symptoms of pink eye, only to wake up with full-blown symptoms. This doesn’t mean you “caught” pink eye in your sleep, although you can get it from a co-sleeping partner. If your symptoms appear suddenly in the morning, it usually means the infection was incubating while you slept.

When your body is at rest, your immune system releases white blood cells called leukocytes. Leukocytes fight off infections such as viral or bacterial conjunctivitis. This immune response may bring on symptoms, making you feel worse when you wake up.

When you’re lying down, fluid and pus may also build up in your eyes and leak out. This causes crusty eyelashes that stick to your cheeks.

You may also wake up with symptoms if allergens affect you while you’re sleeping. For example, airborne pollen may come in through a window. Or, you may be sleeping in a dusty room or with a pet you’re allergic to.

The first symptom of pink eye is often a gritty, sandy feeling in one or both eyes. You may feel like you have something in your eye, such as an eyelash, that you can’t rinse out or rub away. Eye pain is also a common early symptom.

As the infection progresses, symptoms can include:

How you manage pink eye symptoms will often depend on the cause. Pink eye is usually because of viruses, which don’t respond to antibiotics. But you can treat bacterial conjunctivitis with prescription antibiotics.

If you start to notice pink eye symptoms, you can try the following at-home treatments and tips to reduce symptoms:

  • Place a warm or cold damp compress on your eyes.
  • Use artificial tears to lubricate your eyes and eliminate dryness.
  • Take over-the-counter anti-inflammatory or pain-reducing medications.
  • If you wear contact lenses, stop using them until your symptoms go away. You might want to contact an eye doctor before doing so.
  • Avoid using makeup on and around your eyes.
  • If your pink eye is because of allergies, take oral or eyedrop antihistamines.

See a doctor if your condition worsens or you don’t respond to at-home treatment within a few days to a week.

Newborns, young babies, and people with compromised immune systems should see a doctor as soon as symptoms start.

Any of these symptoms should trigger a call or visit to a healthcare professional:

  • significant or unmanageable pain
  • hazy or blurry vision that doesn’t go away when pus or discharge is removed
  • fever
  • extreme sensitivity to light
  • intense redness
  • flu-like symptoms
  • excessive mucus or pus production

It can be hard to identify the root cause of pink eye without a doctor’s input. If you think you or your child may have a bacterial infection, see a doctor. If they confirm bacterial conjunctivitis, they can prescribe antibiotics. Tell them if your symptoms don’t improve after taking antibiotics for a few days.

Some serious viral infections can also cause pink eye. If you or your child has pink eye that may be because of chickenpox (varicella-zoster virus) or herpes simplex, see a doctor.

Pink eye typically goes away within 1 to 2 weeks, with or without medical treatment. You’ll remain contagious for as long as you have symptoms, especially eye discharge.

If you have bacterial pink eye, the American Optometric Association notes that symptoms may start to improve within 3 to 4 days of taking antibiotics. But you still need to take the whole course.

Pink eye prevention tips

To prevent catching or spreading pink eye, consider the following tips:

  • Avoid contact with people who may have pink eye.
  • Wash your hands often and thoroughly with soap and water.
  • Avoid rubbing or touching your eyes.
  • Throw out old makeup that may harbor bacteria.
  • Avoid sharing makeup, towels, or eyewear with others.
  • Disinfect contact lenses thoroughly, according to the manufacturer’s directions.

Pink eye (conjunctivitis) is a contagious eye infection usually caused by viruses or bacteria. Allergies or chemicals may also cause noninfectious pink eye.

Depending on the cause, symptoms may appear very suddenly. With viruses or bacteria, it can take several hours to several days for symptoms to appear. But with allergic pink eye, symptoms can come on suddenly.

Pink eye usually clears up on its own within a couple of weeks. See a healthcare professional if your symptoms are severe or don’t go away with at-home treatment.