Testing a medication to ease depression in veterans with Parkinson's disease

This study is testing whether a medication called ketamine, delivered intravenously as a single dose, can quickly reduce depression in veterans living with Parkinson's disease. The researchers want to understand not only whether the medication works, but also how it works in the brain—specifically, whether it helps restore connections between brain cells and reduces harmful inflammation. The study will compare ketamine to another intravenous medication to make sure the results are fair and trustworthy.

Many people with Parkinson's disease struggle with depression, and standard antidepressant pills don't work well enough for everyone. Research suggests this medication might act quickly—within hours—to improve mood, and scientists want to understand the brain mechanisms behind that improvement so they can better help future patients.