People who borrow money from doorstep lenders should get the same protection as those with payday loans, a charity has argued.
Citizens Advice said copying the rules that stop payday loans being rolled over time after time would stop others falling into a spiral of debt.
More than 1.6 million people use home credit loans in the UK.
The City regulator is reviewing the rules about high-cost credit, including the effect of building up these loans.
In January, the regulator – the Financial Conduct Authority (FCA) – said it was concerned that some people could end up paying a much higher interest rate after merging old and new doorstep loans.
Now they have confirmed to the BBC that "doorstep lending is one of the areas of high cost credit we have identified as having potential issues".
"As we made clear in January, we have concerns about the impact on consumers who take out repeat loans," it added. "We intend to publish our conclusions in May and take action where we find harm.
"In the meantime we expect all lenders to check loans are affordable for customers rather than just assessing the credit risk to themselves."
Citizens Advice said it had helped 30,000 people with doorstep loan debt in the last year.
Only one third of them had a job, it said, and half were in arrears on council tax – a priority bill.
Cases included a woman with severe learning difficulties who had debts from a doorstep lender of £3,016, and who had received an offer of more loans despite the lender being told by a social worker that that an appropriate adult needed to be present for financial decisions.
The charity wants to see new rules for the sector that would follow the regulations covering payday loans, so the number of rollover loans would be limited and borrowers would never pay more than twice the amount that they borrowed.
The conclusions of the FCA review into high-cost credit will be published in May.
The FCA took over regulation of consumer credit four years ago, and since then has introduced new rules for the payday sector and credit card market.