Writing Feedback / Help With Drugs and Alcohol Psych Class Thesis Statement [2]

There is no prompt, except that it needs to address drugs in some way and needs to be 6 pages APA style.

I have many topics I am willing to consider. Such as, depression and the use of anti-depressants, bi-polar and the use of anti-psychotics, and the potential medicinal uses for cannabis. The only issue now is that I have no clue how to form these topics into a working thesis statement. I understand what a thesis statement is, but I am not sure how to create an argumentative thesis about these topics. Can anyone help me? Please and thanks a million!