Herbs for Parkinson's While on DBS?

My husband has Parkinson's and has the DBS, but he still shakes a lot. He wants to start taking herbs. What ones do you suggest and what are their effects? What about glutathione?

Deep brain stimulation (DBS) is a surgical procedure used to treat Parkinson's patients to help them with their tremors, rigidity, slowed movement and walking problems. DBS uses an implanted neurostimulator to block brain signals that cause the symptoms.
We have previously answered questions about using herbs for Parkinson's. Please see our website www.richters.com . Choose Q&A from the main menu, then enter "Parkinson" for the search.
I do not know how the herbs, or glutathione therapy, would interact with the DBS. You will need to consult with your doctor.