I personally could not take it medicinally. I used to bake edibles with half a gram or more at a time and spend hours in outer space. If I went back to it, I'd be back at that again in no time.
I think the risk would be tolerance. If you start to require higher doses for relief, I think it's possible that eventually you'll reach the threshold where you start experiencing side effects. The withdrawal from marijuana can be bad, it was for me. Depression, anxiety, paranoia, mood swings, irritability, insomnia. I felt like I was going insane.