From the book of "Catechism of the Catholic Church": Temporal Punishment is the unhealthy attachment to creatures, which is a consequence of sin. We must be purified through conversion.
I would get them to stop doing what they are doing that is bringing the evil spirits into their lives which is often times drugs and prescribe a moderate amount of medication if it helps.
Have you even thought this through? If schizophrenia is a punishment for sin, don't you think it would afflict more than 1% of the population? Or is it just the punishment for using drugs?
What's the punishment for theft? Herpes?