Every few months I like to give my snakes a dose of pedialyte, or if I wanted to give a calorie booster, typically I just inject it into the rodent, its less stessful then sticking a tube down the poor snakies throat. Also when I worm any snake I inject the rodent with the dewormer. Rodents are a great way to get any oral medecine/supplement into the snake without any added stress
What I do is either put the rodents on its back and stick the needle as far as I can in its stomach at a 15 degree angle (towards the head) and inject, or in smaller prey items (pinkies, etc) you can put it in through the mouth. Hope this helped