An online petition organised by the New Zealand Medical Students' Association calling for the removal of a new loan cap had nearly 19,000 signatures last night.
The association said the seven-year loan cap would start to affect students gradually from late this year.
It started the petition a week ago. Some medical students have already drawn down loans for other degrees before starting the six-year course.
Association president Elizabeth Berryman, of Dunedin, said the cap would ultimately cost taxpayers as it would prevent young doctors from graduating.
''The Government invests a lot in training doctors, but when this policy prevents a large portion of the class at the final hurdle he is completely undermining the investment the taxpayer makes.''
Tertiary Education Minister Steven Joyce said officials would monitor the impact of the policy. Student loans had to be fair to both students and taxpayers, he said.
''Medical students earn the highest income of any student once they graduate.''
The New Zealand Medical Association issued a statement last week supporting the students' campaign.
