I don't know of PD meds that enable stairs, especially dowm. But late stage PD doesn't respond to meds other than dopamine replacement and that doesn't allow people to walk up and down stairs. Any PD patient who can handle stairs will probably die of something else (or complications from a fall) 20 years later.
Since the election we have only seen brief clips of her. All the really bad stuff has happened off camera, so who knows? As I mentioned before she has broken a toe, a wrist, and now has a back brace all in less than a year..