Jester,
Back in 1990 I also had kidney problems while pregnant. It was only on the right side, but then, I was only carrying one baby.
Was in and out of the hospital often too. It started when I was 4 or 5 months along. The uretur had a "kink" in it and the baby was pressing against that area. They did a surgery using the much loved epidural so I wouldn't be sedated with harmful drugs. I was able to watch the whole show and knew the whole time that the baby was also fine since the anestesiologist was monitoring both of us!
They placed a stent (small tube) through the bladder into the uretur and the kidney started flowing. The flank pain continued like there was a bruise there but I urinated what seemed like constantly.
There was discomfort with the uretur since there was a wire attached to it leading to the bladder and it would "tickle" the area that gave me the sensation I had to urinate (even though I really didn't). It was sometimes unbearable, but there was a baby at stake.
For pain, they gave me opium suppositories and they helped alot.
You mentioned dangerous drugs...I know there are certain drugs they can use during certain times during the pregnacy. Morphine as an example might be allowed during one trimester, but not another. OB docs usually know which they can use and when.
Tell her to hang in there!
Inccidently, this might be the same thing that's happening with Rob, the guy that's posted a time or two. (without the baby attached, of course!)
He would want to have an IVP done to see how things are flowing as this might be more than a prostate problem going on with him.
Good luck to both your friend and Rob!
DianaJ