I wish you luck with the psychiatrist, and hope you have better success than we did with my father-in-law. Reactions to these drugs are very individual. Keep a close eye on medication levels, especially if they are to take their meds unsupervised. It's easy to over-medicate elderly folks. I'm experiencing this with my own father just now. He's been taking Xanax for anxiety following a heart attack and some legal problems. He's been taking it too liberally, and my brother and I are fighting him tooth and nail to reduce his dose. He's a hazard to himself (wobbly on his feet, impaired judgement) and we don't want him to put himself in a wheelchair or worse.
My major frustration is that neither parent has a clue that they indeed require help....my mother is in her little dream world, thinking that she could take care of everything, and my father's memory is so bad that he thinks he gets himself up to go to the bathroom (8 or 10 times a night, by the way) and insists that he showers himself - which, of course he doesn't....he can't take three unassisted steps without taking a header.
So, every few days both of 'em gang up on the caregivers ("firing" them, etc.) and it's at the point where they'll drive them away, leaving us no option than "the home".