Peace be upon you. The amount borrowed does not require khums because it is not considered profit. If you purchase something with this money, khums is also not required on that. However, if you start paying the loan installments from profits earned during the year, and the loan is still outstanding, or its equivalent is available and not part of your necessities, or if the loan was used as capital for trade, then khums is due on the amount you paid from the installments.