Dear Patricia, I hope your situation has stabilized. Lithobid is a slow release form of Lithium. Ataxia and tremor are both potential complications of taking Lithium - not a pleasant thought when you also compound it with usual locomotion problems associated with PD. At bare minimum, if your physician hasn't discontinued the drug, you should have a Lithium level drawn as soon as possible. By the way, Lithium toxicity can result also from decreased fluid intake. If you are on a diuretic, you would also exercise caution. Good luck and let me know how things turn out. Tim Hodgens *** Tim Hodgens, Ph.D. Psychologist Westborough, MA