What is the role of pharmaceutical companies in the sudden increase, and epidemic proportions, of mental illness in North America?

1) Why is social life being medicated?
2) What is the role of pharmaceutical companies in the sudden increase, and epidemic proportions, of mental illness in North America?
3) Why behaviour that may be caused by lead poisoning and other toxicant substances are called mental illnesses, instead of physiological poisoning?
4) Is there any correlation between the mental health epidemic and the development of a multibillion dollar mental health pharmaceutical industry in the North America, particularly in the USA and Canada?
5) To what degree does the mental-health-pharmaceutical-industry fashions our mental health reality?