Im an RN and as far as I know antabuse does take longer than that to clear your system, I think you need a second opinion. His advice regarding your drinking does seem a little ambiguous and im not surprised your confused. Im guessing if he's been your GP since you were a child he's an older guy and his practice may not be as up to speed as a younger member of the practice fresh out of medical school or a GP a bit more current in updating their practice skills. It is all too common with older GP's in UK practices. All the best xx