From the Guidelines
For allergic conjunctivitis, dual-action antihistamine and mast cell stabilizer eye drops like olopatadine (Pataday, Patanol) or ketotifen (Alaway, Zaditor) are recommended as first-line treatments. These medications work by blocking histamine receptors and stabilizing mast cells to reduce itching, redness, and swelling 1. Use 1-2 drops in each affected eye, typically once or twice daily depending on the specific product.
Key Points to Consider
- Artificial tears can also help flush allergens and provide relief between medicated drops.
- For more severe cases, prescription-strength options include mast cell stabilizers like cromolyn sodium or combination antihistamine/mast cell stabilizers.
- Steroid eye drops such as loteprednol may be prescribed for short-term use in severe cases, but should only be used under medical supervision due to potential side effects like cataract formation, elevated IOP, and secondary infections 1.
- When using any eye drops, wash hands before application, avoid touching the dropper tip to prevent contamination, and wait at least 5 minutes between different eye medications.
Mechanism of Action
Allergic conjunctivitis is caused by an immune response where mast cells release histamine and other inflammatory mediators when exposed to allergens 1. Dual-action agents possess both antihistamine and mast cell stabilizer activities, generally have onset of action within 30 minutes, and are suitable for acute and longer-term treatment of allergic conjunctivitis symptoms 1.
From the FDA Drug Label
Directions Adults and children 3 years of age and older: Put 1 drop in the affected eye(s) twice daily, every 8-12 hours, no more than twice per day. Directions adults and children 2 years of age and older: put 1 drop in the affected eye(s) twice daily, every 6 to 8 hours, no more than twice per day if using other ophthalmic products while using this product, wait at least 5 minutes between each product ANTIHISTAMINE EYE DROPS UPTO 12 HOURS EYE ITCH RELIEF The recommended eye drops for allergic conjunctivitis are:
- Ketotifen (OPHTH): for adults and children 3 years of age and older, put 1 drop in the affected eye(s) twice daily, every 8-12 hours 2
- Olopatadine (OPHTH): for adults and children 2 years of age and older, put 1 drop in the affected eye(s) twice daily, every 6 to 8 hours 3 Key points:
- Always follow the instructions and precautions on the label
- Consult a doctor for children under the recommended age 2, 3
From the Research
Recommended Eye Drops for Allergic Conjunctivitis
The following are some of the recommended eye drops for allergic conjunctivitis:
- Topical antihistamines, such as levocabastine, emedastine, and azelastine, which provide faster and superior relief than systemic antihistamines 4
- Topical multiple-action histamine H(1)-receptor antagonists, such as olopatadine, ketotifen, and epinastine, which have been shown to prevent activation of neutrophils, eosinophils, and macrophages, or inhibit release of leukotrienes, platelet-activating factors, and other inflammatory mediators 4, 5
- Mast cell stabilisers, such as sodium cromoglicate, nedocromil, and lodoxamide, which may be considered for treatment, although they generally have a slower onset of action 4, 6
- Dual-action agents, such as olopatadine, azelastine, and ketotifen, which combine antihistaminic and mast cell stabilizing effects, and have been shown to be effective in treating seasonal and perennial allergic conjunctivitis 5, 7, 8
Key Characteristics of Recommended Eye Drops
Some key characteristics of the recommended eye drops include:
- Fast and superior relief from symptoms, such as ocular itching and redness 4, 5
- Anti-inflammatory properties, which can help to reduce the severity of allergic reactions 4, 5
- Mast cell stabilizing effects, which can help to prevent the release of histamine and other mediators 4, 7, 8
- Dual-action effects, which can provide both antihistaminic and mast cell stabilizing effects 5, 7, 8
Comparison of Different Eye Drops
Some studies have compared the efficacy of different eye drops for allergic conjunctivitis, including:
- Olopatadine versus ketotifen, which showed that olopatadine was more effective in reducing symptoms of allergic conjunctivitis 5, 6
- Azelastine versus placebo, which showed that azelastine was effective in reducing symptoms of allergic conjunctivitis 6
- Epinastine versus olopatadine, which showed that epinastine was equal or more effective than olopatadine in reducing symptoms of allergic conjunctivitis 5