Okay, I forgot to suggest food.
If you wanted to go really low protein then you would need to go with Science Diet L/D canned, Royal Canin LS 14 (both prescription) or Natural Balance Vegetarian. I'm sure there are other though.
Since there is no diagnosis, I would go moderate protein (somewhere about 20%-25% for kibble) which would be safe even if she doesn't have a liver problem. Red meat is not recommended (along with a few other things).
Depending on how high the bile acids are, you may want to go low protein for a month and use Denosyl.