The NHS has been criticised for having no system for matching overseas graduates to vacancies.
Peter Trewby of the Royal College of Physicians said there was no way of informing junior doctors thinking of coming to the UK of current job competition.
So despite the NHS's continued reliance on overseas staff to fill a third of junior doctor roles, many of these graduates who come to the UK can expect long periods of unemployment, he said.
Writing in the British Medical Journal (BMJ), Trewby said: "The tragedy is that the countries that these doctors come from are in far greater need of their skills.
"Yet what is actually happening is they are spending longer periods of time here unemployed, filling in application forms for six months or a year or sometimes even longer."
BMJ statistics show that there are 210 applicants for each junior doctor advertisement in the UK, with eight recent jobs attracting more than 1,000 applications.
A Department of Health spokesperson said: "The department is addressing these issues and there is already a great deal of information available to doctors on obtaining their first post in the NHS, which highlights that there is considerable competition for these posts.
"This will help them make an informed decision about whether to come to the UK or not."