I have no personal preferences (this idea terrifies me), so go with whatever inspires you!

With b), there is the practical issue that some psych meds will take a certain amount of time to wear off, and/or cause withdrawal symptoms (or even a rebound worsening of some mental symptoms), depending on the med. So you may want to factor that in.

OTOH, if you're using science fictional meds, you can make it up as you go along *g*.