What Is Pinkeye?
The term "pinkeye" is often used to describe any condition that makes the whites of the eyes appear pink or red. There are many causes, but the most common is conjunctivitis (inflammation of the conjunctiva, which is the layer of tissue overlying the white of the eye). The two most common causes of conjunctivitis are infections (for example viral or bacterial) and allergies.
What Causes Pinkeye?
Pinkeye is most often caused by contagious viruses associated with the common cold. Bacteria, fungi, and parasites can also cause infectious conjunctivitis. Allergic conjunctivitis is also common and can be in response to allergens (irritants) in the air or in products placed directly on or near the eyes (such as eye medications or cosmetics). Several other conditions can give the conjunctiva a pink or red appearance, ranging from dry eye and foreign bodies to vision-threatening conditions such as elevated eye pressure, autoimmune disorders, and circulatory problems. In some cases, the eye becomes red secondarily due to a problem in the eyelid such as blepharitis or a stye. Your eye doctor can sort out the cause with a complete eye examination. In newborns and infants, the most common cause of pinkeye is bacterial infection, requiring prompt medical treatment.
What Are Risk Factors for Pinkeye?
The risk of contracting the more common viral pinkeye increases with exposure to other people with pinkeye, as the viruses that cause this condition are highly contagious. Often there's a history of a recent cold or exposure to other people with colds. Poor hygiene in general is also associated with increased risk, and this is especially the case for contact lens wearers.
What Are the Signs and Symptoms of Pinkeye?
Infectious conjunctivitis can cause blurred vision (especially if it also involves the cornea), eye pain, and light sensitivity. People often complain of watery eyes, and there can be discharge (watery, mucus-like, or pus-like). It may affect one or both eyes. Allergic conjunctivitis is frequently accompanied by itchiness and watery discharge. It may be seasonal and is usually bilateral.
What Does Pinkeye Look Like?
The whites of one or both eyes appear pink or red. Edema (swollen lining of the eye from fluid accumulation in the conjunctiva) can give the appearance of puffy eyes. There may be discharge, such as tears, mucus, or pus. The discharge may stick to the lashes, and there may be redness of the eyelid.
What Other Conditions Mimic Pinkeye?
An eye can become pink or red because of irritation (for example from chemical exposure or a foreign body) or from an abrasion (scratch) of the eye's surface. Dry eye is another common cause of eye redness. Overuse of decongestant eye drops can produce rebound redness when the decongestant effect wears off. Less common but potentially more serious causes of red eyes include uveitis (inflammation inside the eye, sometimes related to autoimmune disorders), elevated eye pressure (glaucoma), compromised blood supply to the eye (ischemia), and others. A small blood vessel in the conjunctiva can also leak blood that becomes trapped under the conjunctiva. These red "subconjunctival hemorrhages" are sometimes confused with conjunctivitis. They can be associated with trauma, high blood pressure, or blood thinners. They are typically painless and clear up on their own.
How Long Does Pinkeye Last?
A typical viral conjunctivitis begins in one eye and spreads to the other eye within a week. It usually takes approximately five to 10 days to resolve. Bacterial conjunctivitis usually requires treatment with antibiotics. The time it takes to resolve varies depending on the organism. Allergic conjunctivitis typically lasts throughout the allergy season but can be managed with allergy medications.
What Specialists Treat Pinkeye?
Most primary care providers, including family practice physicians, pediatricians, and internists, can evaluate the eyes and initiate treatment, but if more extensive examination with special equipment is required, particularly in cases that are severe or associated with decreased vision, an eye doctor (optometrist or ophthalmologist) should be consulted.
How Do Health Care Professionals Diagnose Pinkeye?
A thorough eye examination is important to diagnose the cause of pinkeye. Clues that help determine the cause include a history of exposure to other people with pinkeye or a recent cold (accompanying congestion, runny nose, and sneezing are highly suggestive of a contagious virus), contact lens wear (raising concern for both bacteria and fungi), the type of discharge, the presence or absence of blurred vision and sensitivity to light, recent exposure to chemicals or a foreign body, and any associated medical conditions (diabetes, high blood pressure, autoimmune disorders, as well as eye diseases such as glaucoma, uveitis, and more).
The doctor will look for additional clues on the examination. Examples of other findings might include presence of a foreign body or abrasion, swelling and small bumps on the back of the lids that are typically seen with allergy, keratitis (conditions affecting the cornea), and dry eye, among others. In some cases of suspected infection, cultures may be helpful in identifying the organism.
What Is the Treatment for Pinkeye?
In most cases of viral conjunctivitis, no medication is needed as it resolves on its own within two weeks. Medication may be prescribed if the virus affects the cornea (as in the case of herpes virus, for example).
Bacterial conjunctivitis requires antibiotics. Examples include ciprofloxacin (Ciloxan), levofloxacin (Quixin), erythromycin (Ilotycin), azithromycin (AzaSite), ofloxacin (Ocuflox, Floxin), besifloxacin (Besivance), tobramycin (Tobrex), moxifloxacin (Vigamox), polymyxin B, and others. Your doctor will select the treatment based on the suspected type of bacteria, and in some cases, cultures may be necessary to identify the bacteria.
Allergic conjunctivitis responds to antihistamine and/or anti-inflammatory medications. Certain inflammatory eye conditions are treated by placing drops of the steroid prednisolone into the eye (for example, Omnipred) or other steroids. In each case, the treatment is tailored to the suspected cause.
Are Over-the-Counter Eyedrops or Medications Effective for Pinkeye?
Artificial tears (particularly those that are preservative-free) are generally safe, and although they may not cure the pinkeye, they often help alleviate the symptoms somewhat. Ocular decongestants (drops labeled as "redness relievers") should be used only sparingly as they may mask the symptoms and in some cases worsen the condition by contributing to dryness or irritation. For allergic conjunctivitis, several types of over-the-counter medications are available and are in most cases very effective.
Are Home Remedies Effective for the Treatment of Pinkeye?
Cold compresses (for allergy) and warm compresses (for infection) can provide some comfort.
What Is the Prognosis for Pinkeye?
Common viral conjunctivitis usually resolves completely. Infections involving the cornea may leave a permanent scar that affects vision. Certain untreated or undertreated infections or inflammatory conditions can lead to serious and irreversible complications, including loss of sight, so it is particularly important to seek medical care for any pinkeye that is associated with decreased vision, or one that persists beyond a couple of weeks.
Is It Possible to Prevent Pinkeye?
The single most important way to prevent a contagious pinkeye is to wash hands frequently. Unfortunately, once a viral conjunctivitis begins in one eye, it is likely the other eye will become affected soon after. The virus has an incubation period in which the virus can spread prior to the onset of symptoms, making prevention difficult. In spite of this, it is still a good idea to practice good hygiene by minimizing exposure to the affected eye's tears and secretions. This means, in addition to frequent hand washing, you should avoid eye rubbing, consider changing your pillowcase and towels daily, and dispose of any tissues that come into contact with the eye. Ask your doctor if you should dispose of contact lenses and cases or eye makeup.
Azari, A. A. and N. P. Barney. "Conjunctivitis: a systematic review of diagnosis and treatment." Journal of the American Medical Association 310.16 (2013): 1721-1729.
Jhanji, V., T.C. Chan, E.Y. Li, K. Agarwal, and R.B. Vajpayee. "Adenoviral keratoconjunctivitis." Surv Ophthalmol 60.5 September-October 2015: 435-43.