boxer puppy sick wont eat

hi my 5 onth old boxer puppy has been throwing up he will not eat and is very weak  and i dont know what is wrong

[Tammy2009]

You need to see a vet!  He is probably dehydrated and needs fluids.  There are many things that can cause him to be sick, parvo being one of them.  

[chasha33]

Has he had all of his vaccines?You need to keep him hydrated.You could try and see if maybe he would eat some rice and chicken broth.I would let your vet check him as soon as possible.At that age it is hard to say what the problem could be.Has he been Dewormed?