9 yr old male boxer constant vommiting and addicted to water but throws it right up anywhere from 10 minutes to 1 hour. reeper has lost 16 lbs. in 3 weeks hes been to the sj animal hospital twice and i just took him to V.S.D.S. in central nj they cant find anything wrong without surgery!! please advice before 2 late..  I noticed this problem after he was at the vet for a urinary trak infection 4 weeks ago the medicine he was on i belive was baytrill..