Chemosis

Chemosis (or conjunctival chemosis) is a blister-like swelling of the conjunctiva, the clear membrane that covers the whites of your eyes. This symptom is most likely to happen with infections, allergies or injuries. It’s usually treatable and not serious. While it’s unlikely to be dangerous, it’s best to get it checked and treated sooner rather than later.

Overview

What is chemosis?

Chemosis, also known as conjunctival chemosis, is the swelling of your conjunctiva, the clear membranes covering the whites of your eye and the inside of your eyelids.

Your corneas protect the pupils and irises of your eyes. Your conjunctiva are the outermost protective layer for the rest of the surface of your eye. Your conjunctiva also wrap around and cover the inside of your eyelids.

Chemosis can be hard to see unless you look closely. Smaller areas of chemosis on the white of your eye can look like a small, raised area or blister. These often have a slight yellowish tinge to them. Chemosis on the conjunctiva lining the inside of your eyeball can make your eyelid look puffy or swollen. When it’s severe, you might have trouble closing your eyes.

Advertisement

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

Possible Causes

What are the most common causes of chemosis?

Chemosis happens when something damages or irritates your conjunctiva. Your body responds by sending additional fluid, blood cells, immune cells and more to the affected area. These things cause swelling.

Some of the most common causes are:

  • Infections. Bacteria and viruses can affect your conjunctiva. This causes conjunctivitis (often known as “pink eye”). It can also happen with infections around your eyes, like orbital cellulitis.
  • Allergies. Pollen, animal dander, foods and other allergens can cause chemosis.
  • Injuries. Damage to the conjunctiva from an injury can cause them to swell. That can be from foreign objects like your fingernails or airborne items like splinters from wood or shavings from metal (which is why eye protection is key when using tools).

Less common causes include:

  • Chemical and particle irritants. Pollutants like smoke, soot or dust can land on the conjunctiva and irritate them. If it’s severe enough, that can cause swelling. Chemicals — like those in household cleaners — may also cause it if you get them in your eye.
  • Complications from medical procedures. Surgeries on or around your eyes can sometimes lead to chemosis. An example of a surgery like this is eyelid surgery (blepharoplasty).
  • Autoimmune conditions. An example is Graves’ disease, a condition where your immune system attacks your thyroid gland. Graves’ disease can also cause eye symptoms, including chemosis.
  • Nerve conditions. Damage to your abducens nerve, which controls eye movement, can cause chemosis.
  • Medications. Some medications can cause chemosis as a side effect. This is especially true if you’re sensitive or have an allergy to something in medicated drops or ointments.
  • Heart failure. Having heart failure can cause fluid buildup throughout your body (hypervolemia). That can include chemosis because of fluid buildup in your conjunctiva.

Care and Treatment

How is chemosis treated?

There are many possible causes of conjunctival chemosis, and their treatments vary widely. Some examples of treatments include:

  • Antibiotics. These can help with chemosis from a bacterial infection.
  • Anti-inflammatory medications. As these decrease inflammation, they can also help with swelling.
  • Cold packs or icing. Using cold packs to reduce swelling is a common home remedy for minor swelling.

Other treatments might be necessary depending on what caused your chemosis. Your healthcare provider or eye care specialist is the best source of information about the treatment options they recommend for your specific case.

What can I do at home to treat chemosis?

Conjunctival chemosis is often treatable when it’s mild or happens with causes that aren’t severe. The three main things you can do to treat it are:

  • Apply cold packs. You can apply a bag of frozen vegetables wrapped in a towel or a cold pack to your face for 20 minutes at a time to help reduce swelling. Don’t apply ice packs to your skin directly or for over 20 minutes. Doing so could cause more damage or even frostbite-like symptoms.
  • Use artificial tear drops. These can increase eye lubrication and moisture, which can ease some of the symptoms.
  • Take over-the-counter allergy medications. If your chemosis is related to a nonserious allergy, taking allergy medications like diphenhydramine (like in Benadryl®) can help treat the reaction.
Advertisement

Can chemosis be prevented?

Some causes of chemosis are preventable, but many happen unpredictably or for reasons you can’t control. The steps you can take to prevent conjunctival chemosis include:

  • Wash your hands. Conditions like conjunctivitis easily spread to your eyes from unwashed hands. This can also help prevent chemosis from chemical irritants.
  • Protect your eyes. Wearing safety glasses or other eye protection is always a good idea when participating in an activity where something could get in your eye.
  • Manage allergies. If you have an allergy or suspect you have one, talk to a healthcare provider. They can determine if you have an allergy or refer you to an allergist who can help.
  • Don’t rub your eyes. If something is irritating your eye, it can be very hard to resist the urge to rub it. But doing that could make the problem worse or cause damage that leads to chemosis. If you feel like something is in your eye, try rinsing your eye with water. If that doesn’t help, you should get medical attention.

When To Call the Doctor

When should chemosis be treated by a doctor or healthcare provider?

Chemosis needs medical attention when it’s more severe or when it happens with certain causes.

If you experience chemosis and any of the following apply, you should get medical attention as soon as you can:

  • Trouble closing your eye all the way.
  • Blurry or decreased vision.
  • Light sensitivity.
  • Feeling like something is stuck in your eye (even if you can’t see it).
  • A large amount of discharge from your eyes (especially if it’s green or yellow).
  • Eye pain.
  • Bleeding in the whites of your eye.

The above list contains just a few reasons to seek medical care for an eye-related injury or illness. When in doubt, you should always err on the side of caution and seek medical attention. Doing so can help you avoid long-term vision or eye issues.

Advertisement

Additional Common Questions

How long does conjunctival chemosis last?

How long chemosis lasts depends on many factors, especially what’s causing it. Some causes will go away within a few days. Others can last weeks or more. Your eye care specialist can tell you what you should expect with your chemosis and what you can do to make it easier for your eye to recover.

What is the fastest way to get rid of chemosis?

There’s no fast way to get rid of chemosis other than treating whatever is causing it. How long it takes to go away depends on what’s causing it, the treatment(s) you receive and more. Your healthcare provider can tell you about how long it should take to go away and what you can do to make that process happen as smoothly and quickly as possible.

A note from Cleveland Clinic

Just the thought of having blistering or swelling on your eye is enough to make anyone squirm. The most common causes of conjunctival chemosis are short-term conditions that are usually treatable and not severe. Something more serious — like a thyroid or heart problem — can also cause it, but instances like that are rare. If you have chemosis, talk to a healthcare provider. They can tell you more about the likely cause, treatments and what you can do to help it.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 01/29/2024.

Learn more about our editorial process.

Ad
Appointments 216.444.2020