You can also get "one bite" from Ace Hardware store. Be sure to keep it away from the dog as 1 bite is all it takes to get rid of rats and mice.
I had a whole family of rats that gnawed their way into my garage and set up housekeeping. I put out One Bite and they and their babies were all dead within a day or 2. I have not had a problem since. I keep it up away from the dog so she can't get into it. I have not found any more dead critters but every once in awhile I can see where something took a bite out of the stick.
Cherry