II. Epidemiology
- High Prevalence (up to 40% of the U.S. population)
III. Pathophysiology
- Mast Cell and IgE mediated Allergic Reaction
IV. Causes
- See Vernal Conjunctivitis
- Related to seasons or environmental change (esp. spring, summer, fall)
- Recent outdoor exposure to pollen, grass
- Perennial, indoor allergens (e.g. animal dander, Dust mites) may also cause Allergic Conjunctivitis
- Irritants
- Iatrogenic: Topical Antibiotics
- May also cause chemical Conjunctivitis
- Gentamicin and other Aminoglycoside eye preparations
- Sulfonamide eye preparations
- Neomycin eye preparations
V. Symptoms
- Typically bilateral involvement
- Eye itching
- Pathognomonic for Allergic Conjunctivitis
- Eye tearing with stringy discharge
- Eye Fullness Sensation
VI. Signs
- Marked Conjunctival Hyperemia
- Marked Chemosis
- Red hypertrophic papillae on lid Conjunctival lining
- Best seen with Fluorescein
- Appears as cobblestoning
-
Conjunctival edema
- Eye may appear to sink into Conjunctiva
VII. Management: Approach
-
General Measures
- Discontinue offending agents or medications
- Avoid allergan exposures
- Consider Allergic Rhinitis management (oral Antihistamines, Intranasal Corticosteroids)
- Avoid Topical Decongestants
- Mild Symptoms
- Cold compress to eyes
- Artificial tears (preservative-free agents)
- Moderate Symptoms
- Severe Symptoms
- Continue agents used for mild and moderate symptoms as above AND
- Consider Topical Corticosteroid (e.g. loteprednol 0.2% or fluorometholone 0.1%)
- Exercise caution (exclude infection first) and refer to ophthalmology
- Other agents
- Topical NSAIDs (see below)
- Systemic Corticosteroids (short course)
- Immunomodulators (by ophthlamology or allergist)
- Omalizumab (Xolair)
- Cyclosporin A
- Tacrolimus
VIII. Management: Medications
-
Ocular Mast Cell Stabilizers (preferred)
- Cromolyn Sodium (Crolom) 1 drop 4-6x/day
- Lodoxamide 0.1% (Alomide) 1-2 drops each eye four times daily
- Olopatadine 0.1% (Patanol, OTC in 2020) 1-2 drops each eye twice daily
- Ketotifen 0.025% (Alaway OTC, Zaditor) 1-2 drops each eye twice daily
- Less expensive and over-the-counter
-
Ocular Antihistamines
- Naphazoline (Vasocon, Naphcon) 1 drop twice to four times daily prn
- Epinastine (Elestat) 0.05% 1 drop each eye twice daily
- Bepotastine (Bepreve) 1.5% 1 drop each eye twice daily
- Alcaftadine (Lastacraft, OTC as of 2022) 0.25% (2.5 mg/mL) one drop in each eye daily
-
Ocular NSAIDs
- Ketorolac 0.5% (Acular) 1 drop four times daily for 7 days
- Diclofenac 0.1% (Voltaren) 1 drop four times daily
- Oral Antihistamine
- Mild to moderate: Non-Sedating Antihistamine (e.g. Cetirizine)
- Severe: Diphenhydramine (Benadryl)
- Consider Intranasal Steroid
- Consider short course of oral Corticosteroids (3-5 days)
- Indicated for severe, refractory cases
IX. Resources: Patient Education
- Information from your Family Doctor
X. References
- Williams (2017) Crit Dec Emerg Med 31(2): 3-12
- Bielory (2020) Ann Allergy Asthma Immunol 124(2):118-34 +PMID: 31759180 [PubMed]
- Cronau (2010) Am Fam Physician 81(2): 137-44 [PubMed]
- Winters (2024) Am Fam Physician 110(2):134-44 [PubMed]