Widely variable since everyone is different. Some people respond better to certain meds than others, and even if they do get the right med, getting the right dosage is tricky at best.
As for side-effects, well, those also run a wide range. Maybe mood swings, maybe depression, maybe super-hyperactivity to the point of tachycardia and heart attack… really no one answer to that either.
I will say that while some people’s lives are far better due to medication, some of us really have more problems with pills than without. There is no “one size fits all” solution since everybody is different.