Nope. People with dissociative disorders usually take medication to control the symptoms of PTSD, like anxiety, depression, and so on. There are no medications that can suppress, strengthen, create, destroy or fundamentally change the nature of your dissociative parts.
You’re all part of the same physical person, you always will be, and you’ll succeed and fail as a team. NOT by smothering, stifling, or suppressing your parts. They’ve suffered enough.
I was hesitant, but asked everybody today: “If the drug did exist, would you take it?” After some sass about the question being stupid, it was a resounding no.