Tylan can be quite helpful with mild respiratory troubles. I'd recommend using it as directed, in the water. That's how I've always used it to good result.
You know she'll be getting her meds because she won't go long without drinking water. In order to make sure she does drink a good amount each day, I always feed dry food only during treatment so the rat gets thirsty. Also, a touch of fruit juice mixed in helps hide any nasty flavor and makes it very appealing
