I am trying to administer Panacur to a white-line gecko but he won't open his mouth! The first time at the vet he promptly bit the stick with the medication, but now he won't open. I've tried gently prying, squeezing his jaw, even dribbling water on his nose. This is one stubborn lizard! Any other ideas on how to get the stuff into him. I would like to handle him as little as possible because he is not at all tame.