all the admissions info is here: http://sydney.edu.au/medicine/futur...gram/admissions/selection-criteria.php#MD_DMD but basically you need to have a good GPA (5) which is about a credit average and you need to sit the GAMSAT and do pretty well in that, too. it outlines everything so check it out. Also the med faculty are really helpful over the phone if you want to talk to someone about it.
edit: any bachelors degree can be used for admission provided that it meets their assessment, but any medical science degree with a credit average will be fine