When you like someone or something to a point, but after a little while it starts to get on your nerves and continued exposure makes you feel like biting a steel rod in two.
When someone is cool for only a certain amount of time, then you guys start arguing (or maybe they just begin to irritate you), then you can only take them IN DOSES. Some smaller than others. Like medicine, if you take too much it's a bad thing, no?
Guy 1: "It was a pleasure meeting your friend, I appreciate you introducing us truly."
Guy2: " Yeah, he's an alright guy; But I've known him for a while, and he's just someone you gotta take in doses. ya feel me?"
Guy 1: "OOh I appreciate the heads up man!"