The question is, what are these medications, and what do that do? How much do they cost, and what are the side effects? The Infographic below shows the Top 10 Psychiatric Medications prescribed in America in 2011, and includes average costs, disorders treated, and side effects. http://www.rxlist.com/xanax-drug.htm. http://www.rxlist.com/celexa-drug.htm. http://www.rxlist.com/zoloft-drug.htm. http://www.rxlist.com/ativan-drug.htm.
Necessity is the mother of invention. Prov. When people really need to do something, they will figure out a way to do it. When the fan belt on Linda's car broke in the middle of the desert, Linda used her stockings as a replacement. Necessity is the mother of invention.
For the concepts in statistics, see Sufficient statistic. In logic, necessity and sufficiency are implicational relationships between statements. The assertion that one statement is a necessary and sufficient condition of another means that the former statement is true if and only if the latter is true.