McColgan, 24, is working her way back to fitness following ankle surgery and recently lost her UK Athletics funding.
Fellow Scot Libby Clegg, a Paralympic sprinter, also had her funding cut after pulling out of the IPC World Championships.
"When people need the support most, that's when the majority of people are cut," McColgan told BBC Scotland.
"You need that added lifeline to help you when you're down.
"It's one of the unfortunate sides of elite sport. Unfortunately, injuries are going to come along."
UK Athletics, the national governing body for British athletics, offers elite athletes support through its World Class Performance Programme.
Funded by the National Lottery through UK Sport, selection is based upon the potential to win medals at an Olympic or Paralympic Games and is split into two levels: athletes with the potential to win a medal at Rio 2016 and athletes developing towards Tokyo 2020.
"The problem we have is that funding is based on Olympic medal potential. Looking at the list, realistically there aren't that many athletes that will medal," said steeplechaser McColgan.
"You're talking the very highest ranked people: Mo Farah, Jess Ennis, Greg Rutherford. But, aside from that, it's very difficult to claim that everyone on that list has the potential to medal, that's the truth.
"If people are making GB teams then they should be supported in some way, shape or form."
McColgan made the GB team for the 2012 Olympics, although she failed to reach the 3,000m steeplechase final in London, and was sixth in the Commonwealth Games final in Glasgow last year.
However, she last competed in January and had screws inserted in her ankle during surgery.
"There are many athletes that have gone to the World Championships in 2015 and previous Olympics that aren't funded and aren't supported," added McColgan.
"Even just medically, some physio, some scans, it doesn't always have to be financially driven.
"A lot of the general public believes that everyone that makes the GB team are well supported.
"It isn't like that at all, unfortunately. It really is down to people's opinions of who is Olympic potential or not and sometimes that's quite a difficult concept to put together."
Scottish middle-distance runner Eilish McColgan has called for more support for athletes returning from injury.