Allergic Conjunctivitis

Summary about Disease


Allergic conjunctivitis is inflammation of the conjunctiva (the membrane lining the eyelid and covering the white part of the eye) caused by an allergic reaction. It is not contagious and typically affects both eyes. The allergic reaction occurs when the eye comes into contact with an allergen.

Symptoms


Common symptoms include:

Itching (primary symptom)

Redness

Burning

Tearing

Swollen eyelids

Sensitivity to light (photophobia)

Stringy discharge

Causes


Allergic conjunctivitis is triggered by allergens such as:

Pollen (grass, trees, ragweed)

Dust mites

Pet dander

Mold spores

Cosmetics

Contact lens solutions

Certain medications

Medicine Used


Treatment options include:

Artificial tears (to wash away allergens and lubricate the eyes)

Antihistamine eye drops (e.g., olopatadine, ketotifen)

Mast cell stabilizer eye drops (e.g., cromolyn sodium, lodoxamide)

Decongestant eye drops (short-term use only, e.g., naphazoline, tetrahydrozoline)

Corticosteroid eye drops (for severe cases, use under doctor's supervision)

Oral antihistamines (e.g., cetirizine, loratadine, fexofenadine)

Is Communicable


No, allergic conjunctivitis is not contagious. It is caused by an allergic reaction, not an infection.

Precautions


Avoid known allergens whenever possible.

Keep windows and doors closed during high pollen seasons.

Use air purifiers with HEPA filters.

Wash bedding frequently in hot water.

Avoid rubbing your eyes.

Use preservative-free artificial tears frequently to flush out allergens.

If you wear contact lenses, clean them properly and consider using daily disposables.

How long does an outbreak last?


The duration of allergic conjunctivitis depends on the allergen exposure.

Seasonal allergies (e.g., pollen) can last for weeks or months during the allergy season.

Perennial allergies (e.g., dust mites, pet dander) can be present year-round, with symptoms fluctuating depending on exposure levels.

With treatment and avoidance of allergens, symptoms can subside within a few days to weeks.

How is it diagnosed?


Diagnosis is usually based on:

Medical history and allergy history.

Symptoms.

Physical examination of the eyes.

Allergy testing (skin prick tests or blood tests) may be performed to identify specific allergens.

Timeline of Symptoms


Immediate: Itching, tearing, redness typically begin shortly after exposure to the allergen.

Within hours: Swelling of the eyelids may develop.

Days/Weeks (if untreated or allergen exposure continues): Symptoms persist and may worsen, leading to discomfort and potential interference with daily activities.

Important Considerations


Consult an eye doctor (ophthalmologist or optometrist) or allergist for diagnosis and treatment.

Long-term use of decongestant eye drops can lead to rebound congestion and should be avoided.

Corticosteroid eye drops can have serious side effects and should only be used under the supervision of a doctor.

If symptoms are severe or do not improve with over-the-counter treatments, seek medical attention.

Distinguish from other types of conjunctivitis (e.g., viral, bacterial) which are contagious. Allergic conjunctivitis is not.