How long ago was he treated?
How long has he been lethargic and not eaten?
Any other symptoms such as vomiting or diarrhea?
He was treated a little more than a year ago. he has benn lethargic all afternooon.
he ate but only becase i carried his bowl to him and set it right in front of his face.
Glad you mentioned Promeris- this in particular has caused some bad side effects in dogs. Symptoms like you are describing as well. Let me find some info. for you on it and then we'll decide.
It is absorbed pretty quickly but you can certainly wash him if he is going to be able to get dry and stay warm. This is just a possibility of what may be wrong. I know we have seen some problems in dogs that we believe this is the cause of them.