From Quacks to Quaaludes: Three Centuries of Drug Advertising (2012)
resobscura.blogspot.com
resobscura.blogspot.com
In some cases, they can be more dangerous because far too many people are unaware that the drugs they take are dangerous.
This is the main tell of a snake oil salesman. If someone's selling something that works they don't need to load the pitch with their product's life story and "trust me" statements.