What prescription medication is recommended for an adult patient with itchy eyes?

Prescription Treatment for Itchy Eyes

For adults with itchy eyes due to allergic conjunctivitis, prescribe dual-action topical antihistamine/mast cell stabilizers as first-line therapy, with olopatadine 0.1% (one drop twice daily) or ketotifen 0.025% (one drop twice daily) being the most effective options. 1, 2

First-Line Prescription Options

Dual-action agents are superior to single-mechanism drugs because they provide both immediate symptom relief (antihistamine effect within 30 minutes) and prevent future episodes (mast cell stabilization). 1, 2

Recommended Prescription Medications:

• Olopatadine 0.1%: One drop in each affected eye twice daily—provides rapid onset within 30 minutes and maintains efficacy for at least 8 hours 2, 3
• Ketotifen 0.025%: One drop twice daily—effective within 15 minutes with duration of at least 8 hours 1, 4
• Azelastine hydrochloride: 2-4 times daily for patients over 4 years 5
• Epinastine hydrochloride: Twice daily for up to 8 weeks (patients over 12 years) 5

Olopatadine demonstrates superior efficacy compared to ketotifen for reducing itching, tearing, and hyperemia, with quicker symptom relief by day 4 and fewer side effects (10% vs 18% adverse reactions). 6

Adjunctive Non-Prescription Measures

While prescribing medication, recommend these evidence-based adjuncts:

• Refrigerated preservative-free artificial tears four times daily to dilute allergens and inflammatory mediators 1, 2
• Cold compresses for immediate symptomatic relief 1, 2
• Storing prescription eye drops in the refrigerator provides additional cooling relief upon instillation 1

Second-Line Prescription Options

If dual-action agents are ineffective after 48 hours, consider:

Mast Cell Stabilizers Alone (Prophylactic Use):

• Sodium cromoglycate: Four times daily—safest option with no age restriction but requires several days to achieve optimal relief 5, 1
• Lodoxamide: Four times daily for patients over 4 years 5

These agents are better suited for prophylactic or longer-term treatment rather than acute symptom management due to their slow onset of action. 1, 2

Topical NSAIDs:

• Ketorolac: Provides temporary relief of ocular itching in seasonal allergic conjunctivitis 1

Third-Line Prescription Options (Severe Cases Only)

For severe symptoms unresponsive to dual-action agents after 48 hours, add a brief 1-2 week course of loteprednol etabonate 0.2% or 0.5% four times daily. 1, 2, 7

Critical Monitoring Requirements for Corticosteroids:

• Baseline intraocular pressure (IOP) measurement before initiating therapy 1, 2
• Periodic IOP monitoring throughout treatment 1
• Pupillary dilation to evaluate for cataract formation 1
• Strictly limit duration to 1-2 weeks maximum 1, 2

Loteprednol etabonate provides reduction in bulbar conjunctival injection and itching beginning approximately 2 hours after first dose, with limited systemic absorption (<1 ng/mL). 7

Fourth-Line Options (Refractory Cases)

For severe allergic conjunctivitis (vernal or atopic keratoconjunctivitis) unresponsive to the above treatments:

• Topical cyclosporine 0.05%: At least four times daily—demonstrates reduction in signs and symptoms after 2 weeks 1
• Topical tacrolimus 0.03% or 0.1%: Alternative to cyclosporine, allows for reduced corticosteroid use 1

These agents are particularly valuable for chronic severe disease as they allow reduction or elimination of topical corticosteroid therapy. 1

Critical Pitfalls to Avoid

Do NOT Prescribe:

• Topical antihistamines alone without mast cell stabilization for initial therapy—dual-action agents are superior 1, 2
• Chronic vasoconstrictors (naphazoline, tetrahydrozoline)—cause rebound hyperemia (conjunctivitis medicamentosa) if used beyond 10 days 1, 2
• Topical antibiotics—provide no benefit for allergic disease, induce toxicity, and contribute to antibiotic resistance 1
• Punctal plugs—prevent flushing of allergens and inflammatory mediators from the ocular surface 1

Oral Antihistamines:

Avoid oral antihistamines as primary treatment for allergic conjunctivitis—they may worsen dry eye syndrome and impair the tear film's protective barrier. 1, 2 However, they remain appropriate for concomitant systemic allergic symptoms (rhinitis), and topical therapy provides added benefit even when patients are on systemic antihistamines. 8

Special Populations

Children:

• Sodium cromoglycate: Safe for all ages including infants 5
• Ketotifen: Approved for children over 3 years 5
• Olopatadine: Approved for children over 3 years 5
• Azelastine: Approved for children over 4 years 5

For children 7-17 years with mild-to-moderate symptoms not responding to topical lubrication or antihistamine eyedrops, refer to ophthalmology via standard/routine pathway. 5

When to Refer to Ophthalmology

Urgent referral (within 4 weeks) is indicated for:

• Adults with moderate-to-severe disease unresponsive to topical treatment 5
• Patients requiring tacrolimus 0.1% ointment to lid margins 5
• Any patient requiring prolonged corticosteroid therapy (>8 weeks) 5

Emergency referral (within 24 hours) is indicated for:

• Severe disease with significant risk to visual acuity 5
• Progressive conjunctival cicatrization 5
• Sight-threatening atopic keratoconjunctivitis 1

Duration of Treatment

Unlike topical corticosteroids, dual-action agents have no specified maximum treatment duration and can be used continuously as long as allergen exposure persists. 1 For seasonal allergic conjunctivitis, continue throughout the allergy season. For perennial disease, use continuously with reassessment at regular follow-up visits based on symptom control. 1