Difference Between Pink Eye and Allergies

Pink eye can occur due to many reasons. Allergy is one of those reasons. However, allergic reactions may or may not be restricted to the eye, and severe allergies may result in anaphylactic shock. This article will talk about both pink eye and allergies and the differences between them in detail, highlighting their clinical features, symptoms, causes, investigation and diagnosis, prognosis, and the course of treatment/management they require.

Pink Eye

Viruses and bacteria can result in pink eye. Conjunctivitis, uveitis, irits, elevated pressure in the eye as well as sinusitis can cause pink eye. The commonest cause of pink eye is conjunctivitis. Conjunctivitis can be due to viruses, bacteria, allergies, and chemicals.

Viral conjunctivitis is caused by viruses that cause upper respiratory tract infections. Therefore, it accompanies common cold, sinusitis, and throat inflammation. It features excessive production of tears, itching, pain, and blurred vision sometimes. Pink eye usually starts on one side and spreads to the other. Diagnosis of pink eye is clinical. Antiviral drugs are indicated in severe cases only. Pink eye is self-limiting. Supportive treatments and good hygiene are often enough. It spreads rapidly. Proper hand washing, personal eating utensils, cups, towels and handkerchiefs limit spread.

Bacterial pink eye sets in rapidly. It features redness of eye, excessive tearing, pain, blurring of vision and yellowish discharge. Eye lids stick together due to yellowish eye discharge. Eye and surrounding area may crust over. Some patients feel like there is something in the eyes because of the irritation caused by the discharge. It starts in one eye and usually spreads to the other within a week. Staphylococci and Streptococci are the usual culprits. While these organisms cause more redness, Chlamydia does not cause much redness. In Chlamydial conjunctivitis, there is a false membrane formed on the surface of the eyes and under the eyelids. Bacterial conjunctivitis can be confirmed by taking a swab for culture. Doctors prescribe antibiotics and pain killers without waiting for reports usually.

Chemical causes irritation if they get into the eye accidentally. Eye should be washed thoroughly with clean running water, covered, and the patient should rush to a hospital. Potent irritants like acids and bases can burn the eye and blind the patient permanently. If the pain increases while looking at a bright light (Photophobia), attention should be paid to exclude uveitis, elevated eye pressure, and meningitis. Photophobia is not prominent in conjunctivitis. Acute elevation of eye pressure presents as painful pink eye with photophobia. Meningitis presents as fever, headache, neck stiffness, and photophobia. Sinusitis may cause pink eye due to associated increase of regional circulation.


Allergic conjunctivitis is an abnormal hypersensitive reaction to a normal substance in the environment. eye allergies presents normally after a positive contact with an allergenic substance. There are pain, tearing, irritation, and redness of eye. Sometimes allergy is localized to the eyes but, in some susceptible individuals, even this can progress into a full blown anaphylactic shock. There is a history of asthma, food allergy, or drug allergy in these patients. Avoiding allergens, anti-histamines, and steroids are effective in treating allergic conjunctivitis.

What is the difference between Pink Eye and Allergies?

• Allergies are hypersensitivity reaction to normal substances, which are not harmful to most.

• Infections and irritants cause pink eye in everybody.

• Allergic pink eye goes off when treated with antihistamines and steroids while infective pink eye responds to antibiotics and antivirals.


You may also be interested in reading:

1. Difference Between Viral and Bacterial Pink Eye

2. Difference Between Cold and Allergies