mentally unbalanced

Her emotion was emphasized by a realization that her escort was a mentally unbalanced, drug-mad man.

Had I had none but mentally unbalanced people to talk with, I might have continued to cherish a distorted perspective.

Such a death would have been bad enough, but to meet death at the hands of a man mentally unbalanced!

Perhaps it was true, as she had heard somewhere, that the man was mentally unbalanced; that he had his—well, his bad days.

Their habit of self-abuse had originated and become exaggerated because they were already mentally unbalanced.