Hundreds of nursing students at nine universities have been hit with errors in their student loan payments, the Royal College of Nursing says.
The students have been told they were mistakenly overpaid between £600 and £5,000 by the Student Loans Company and to expect no more payments this year.
The letters came months after money was received and is leaving some students struggling to pay bills and rent.
The Student Loans Company said it was aware of the issues.
It added: "We are also contacting the individual students affected to make them aware of the different options open to them."
Emma Moss, studying at the University of West London, said: "I'm worried sick about being left with barely enough money to pay the rent, buy food and travel to work and university."
She said the money problem was the last thing she needed in the final few months of her nursing degree.
Emma, like many of the others affected, was allegedly overpaid in September. In Emma's case, the amount was £800.
Student loans are usually paid in three instalments throughout the year. This helps students with budgeting.
She said: "When I called the Student Loans Company in September to question my payments they told me that there was no error.
"Now they tell me that I owe almost £800 and will not be receiving my next instalment.
"If they take this money from me, I have no idea what I'm going to do next."
Another student affected, Jessica Sainsbury, said: "The past couple of weeks turned the world upside down. Some of my peers see no other option than to drop out if they are unsuccessful with the hardship fund application from our university."
Ewout Van Sabben, a third-year student of nursing at the University of West London, has been told he was overpaid about £5,000.
The news came as he prepared to present his final year dissertation.
"As well as being extremely upset, students are shocked at how the Student Loans Company have managed this situation, with information sent in dribs and drabs and some students notified weeks after their peers."
Many students have been told they will not get any payments in April, as they would have been expecting, as they had already received the money.
The Royal College of Nursing, which has been supporting student nurses with their problems, has called on the SLC to write off the overpayments in order to avoid putting students into financial hardship.
RCN chief executive Janet Davies said: "Students budget according to loan forecast and a sudden withdrawal of payment can have disastrous results, such as inability to pay rent. This action comes at a critical time when students are studying for exams and projects.
"I am very concerned about the considerable amount of distress and disruption this error and subsequent action is causing. Student nurses, or indeed any students, are simply not in a position to cope with a sharp reduction in expected loan payments."
It appears that the largest overpayments were made to poorer students due to receive maintenance grants as well as fee loans. It is believed the error may relate to changes in the nursing bursary scheme, which was scrapped for new entrants in 2017.