i had a negative reaction to the paste, just saying, so proceed with caution. i woke up one morning and it took a significant amount of time for my eyes to adjust to the kitchen light while i was making coffee and breakfast. i didn't make the connection then. however the next morning, it took half the day to get my eyesight straightened out. it was almost like someone was sliding the dimmer on the light switch up and down. i was freaking out a bit and realized that i had just started a round of pea-sized paste treatments a couple days before and that was likely the cause. i did some internet digging and saw that was a potential side-effect. i stopped taking the ivermectin immediately and i'm not saying i won't take it again ever but i'd have to be in really bad shape to risk that again. take this for what it's worth, thought you'd appreciate something outside of "group think" you often get on these boards.