In his highly entertaining (if chemically and scientifically esoteric) book "Excuse Me Sir, Would You Like to Buy a Kilo of Isopropyl Bromide?", chemical engineer and industrial chemist Max Gergel starts out by describing his university studies, and his (frequently unsuccessful) romantic endeavors, during World War II. In one incident, he describes the breakup of a relationship he'd taken far more seriously than the lady concerned. So upset was he, both physically and mentally, that he sought a doctor's advice.
Dr. Silver was an unusual man. He did not prescribe medicine; he gave shots. These were ordered from outside the city. They were expensive. He had cured Albert Ragsdale's Angioneurotic Edema—with shots; he had treated my mother's hives—with shots. One of Kahn's carpenters stepped off a building and fell through a maze of framing breaking an arm and a leg—he got shots.
I expected shots. No, we sat in his office and he asked me intimate details of my sex life and habits, then walked over to my mother and told her that I had a broken heart. She asked whether he would treat this with shots, but he assured her he had a remedy.
Going to a side shelf he removed a mortar and pestle. In the mortar he put iron sulfate, quinine and Karo syrup. He stirred and ground this mixture vigorously. The product was a thick yellow liquid. He poured this into a bottle, spooned out a generous portion. He then commanded me to think about J., close my eyes and swallow the mess. I did. It was awful, hard to get down, almost impossible to retain. The effect on the epithelial lining of my stomach was disaster. I coughed and burped and struggled for air.
"Good" said Silver. "Think of her again, and that long night you waited for her outside Steward's Hall, and drink another spoonful."
I took the nostrum everywhere I went. Let even the smallest memory of better days—when we were sweethearts—beset me and I would take a swig—and then suffer. After a while the merest thought of J. brought convulsions—without the medicine.
Even as I write this, thirty years later, I feel a twinge. Dr. Silver was a student of Pavlov.
I'd call that a classic example of aversion therapy, all right - as well as a "kill or cure" approach by the doctor!
Max Gergel's book is entertaining, albeit hard to understand in parts for those who don't have a background in chemistry (which would include me). Derek Corante featured another excerpt from them back in 2015. He also linked to a free download of the book (in Adobe Acrobat [.PDF] format), if you're interested. It's long out of print, and used copies are expensive and hard to find.