In your case, no. Your medicine is prescribed by a physician. In your silly comparison, MJ is a schedule 1 controlled substance, meaning it has no recognized medical use and, as such is inconsistent with your case.
Guns or Doobie, take your pick.
But there is no pick.
You can be as clean as a whistle and your are in favor of violating their constitutional rights because of something their neighbor might possibly do.
That is a very democrat point of view.
So?
If I got behind the wheel I could be hauled in for DUI just as fast as someone who sniffed glue. (do they still do that?) They don't care if it is prescribed, only that it lowers your reflex time and impairs your judgment.
That is morally and mentally consistent.
Your position is not.
As an free man...I will pick both.
May your chains rest lightly...