I believe one should not even consider in making a bitcoin related loan if the source of one's income isn't denominated in bitcoin aswell.

Mainly because there could be problems with loan repayment if the value of bitcoin increases during the duration of loan itself, on the other hand; if price would go under; it would
be good for loan taker, but that's a gamble, and as a loan taker you can't afford to gamble.

So use bitcoin loans only if you get income in bitcoins, and for every other case denominate the loan in fiat.