Borrowdale, who was brought to Coventry by Iain Dowie and sold by Chris Coleman, has only made three appearances for Queens Park Rangers this season.
Speaking about his month long loan at Brunton Park, Borrowdale told Carlisle's official club website: "I'm at the stage in my career where I just want to play games, so I saw the move as a good opportunity for me to do just that as chances are a bit limited for me at QPR currently.
"QPR are doing brilliantly this season but for me it's a bit frustrating watching from the sidelines.
"Every player just wants to be out there playing football but at the moment I can't really argue with the manager's team selections as he's got the club right up there at the top of the Championship.
"One of the guys down there knows the manager here and he told me it would be a good move. He said the club likes to play football and that I'll get treated well, and my first impressions are that is definitely the case."