Investigators Review Tolerability of Over-The-Counter Ocular Allergy Drops

An African-American Man is Having Allergy Problems Outside in Nature.
Man of African-American Ethnicity is Rubbing his Eyes Due to Problems with Sight in the Public Park.
The researchers suggested patients may be more compliant using 0.7% olopatadine.

This article is part of Optometry Advisor’s conference coverage from the 2021 meeting of the American Academy of Optometry, held in Boston from November 3 to 6, 2021. The team at Optometry Advisor will be reporting on a variety of the research presented by the primary eye care experts at the AAO. Check back for more from the AAO Optometry 2021 Meeting..

Ocular allergy responses can cause intense itching, intolerable pain, and severe discomfort. So, when patients ask for something to give them relief, the last thing they’re looking for is a drop that will cause them additional discomfort. In that sense, medical tolerability can affect patient compliance and, ultimately, their ocular health. A study presented at the American Academy of Optometry’s 2021 meeting in Boston, held November 3-6, characterized the patient’s comfort at time of application for 2 types of topical, over-the-counter ocular allergy therapeutics; 0.7% olopatadine and 0.035% ketotifen fumarate.

The investigators took into account 107 participants (mean age 25.7±6.8 years; 78.5% women). All participants were minimally symptomatic based on their responses to the Standardized Patient Evaluation of Eye Dryness questionnaire (SPEED). Participants were also required to have a minimal interocular comfort difference of 7 units or less, per the investigator-designed visual analog scale (VAS).

The study was conducted by applying a single drop of 0.7% olopatadine or 0.035% ketotifen fumarate to each participant’s right eye, and the other drop was applied to the left eye. Ocular comfort of each eye was measured with a VAS at 4 points: at the time of instillation, 30 seconds later, 1 minute later, and 2 minutes later. The researchers monitored patients’ visual acuity (in logMAR), and overall bulbar redness.

The VAS results showed patients were more comfortable using 0.7% olopatadine over 0.035% ketotifen fumarate at all time points; 83.3±19.0 vs 66.9±24.2 at instillation (P <.00001), 85.9±15.6 vs 76.6±19.8 at 30 seconds (P <.00001), 89.9±13.1 vs 83.8±17.2 at 1 minute (P =.0001), and 92.2±10.4 vs 89.3±13.6 at 2 minutes (P =.03). The study did not find any difference in visual acuity following drop between the 0.035% ketotifen fumarate (-0.088±0.01) and 0.7% olopatadine (-0.081±0.01) groups (P =.57). However, eyes treated with 0.035% ketotifen fumarate (0.63±0.02) had significantly greater overall bulbar redness than eyes treated with 0.7% olopatadine (0.59±0.02) (P =.003), investigators reported.

“Medication tolerability is a major factor in patient compliance,” the researchers explained. “These data suggest that patients may be more compliant with 0.7% olopatadine than 0.035% ketotifen fumarate allergy eye drops.”

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Logan A, Franklin Q, McGwin G, et al. Understanding ocular comfort differences between Pataday once daily relief extra strength and Alaway. Poster Presented at the American Academy of Optometry 2021 meeting; November 3-6; Boston. Board #26.