Long Lasting Allergy Eye Drops: Our eye drops with active ingredient Ketotifen help relieve eye allergy symptoms caused by ragweed, pollen, grass, dust and animal hair. Relief lasts for up to 12 hours. Effective, Fast Relief: Armas allergy eye drops start working within minutes and work right at the source of eye allergy symptoms, relieving itching, redness and watering faster than most allergy pills.