Effect of L-Dihydoxyphenylserine on Locomotion, Postural Stability, and Fall Risk Reduction in Parkinson Disease

This research study is being done to determine whether treatment with L- Dihydroxyphenylserine (L-DOPS) versus placebo (an inactive substance that looks like study drug) in addition to other Parkinson Disease (PD) drugs will improve balance, walking, and reduce risk of falls and/or severity of falls in PD subjects. The study is also being done to determine the effectiveness, safety, and tolerability of L-DOPS, and whether it will decrease Freezing of Gait (FOG), improve apathy (generalized disinterest) or show a relationship between apathy and slowed movement and fall risk.