Wrong meds causing extreme anxiety, balance issues?

[hersister]

Since last summer my youngest sister has been in a horrible state of anxiety, with several suicide attempts. I posted questions back in Nov. 2009 about having her tested, which we did. The neurologist said the tests came out normal (however she had been put on lithium beforehand, yet he was not concerned about possible false results).
She has been hospitalized several times, was inpatient twice, went through psychiatric "daycare", and nothing has made a difference in her condition. She currently has a psychiatrist who prescribes her meds but she has made NO IMPROVEMENT at all. All of the supposed experts have discharged her, with no real change.

I am quite sure she is on too many and/or the wrong drugs. She is getting worse.
The morning is worst for her as she wakes up in a panic and worries about everything. (By the way, her life is wonderful and she has no financial problems) She is now AFRAID TO SHOWER, and cannot stand up correctly because of balance issues. Her hands shake constantly and she has not smiled in a very long time. She is getting worse, not better.

The doctor has her on these drugs:
Lithium 300 mg (3 per day)
Risperidone 2 mg at night
xanax 1 mg (2 or 3 per day)

WHAT CAN I DO TO HELP HER? Should she change doctors, and if so, how can I help her find someone? It seems we have already tried EVERYTHING and yet her life is passing by because she is miserable.

[MG (Admin)]

What are her most recent lithium levels?
She may be having toxicity from the lithium...but DO NOT make any dose changes without speaking to the treating physician first!

looking forward to hearing back