My 5lb daschihuahua developed swelling to her lacrimal gland (teardrops) one day. I got my sprayer full of colloidal silver (10ppm) and sprayed it 3x. We went about our business and 10 mins later it was gone. I also used this sprayer for my cat's eyes if I noticed a tear trail. He takes 3 sprays directly in his face because he knew it would be good for him. They both drank it freely, too. Animals know it's good for them!