The first thing Abraham Morgentaler learned about testosterone is that it’s a brain hormone. It was in a lab at Harvard, while an undergraduate in the late 1970s, where he had this realization: A castrated male lizard put in a cage with a female would not perform its mating ritual and would be uninterested in the female; but the same lizard, dosed with testosterone in the areas of the brain sensitive to testosterone, would — its dewlap coming out, head bobbing.
That is what he thought about when, about a decade later and a newly minted urologist, he began dosing men with testosterone. The patients were miserable, complaining of a lack of sex drive so severe it was ruining their relationships and lives. They were often coming for a second, third, even fourth opinion, after other specialists had been unable to help.
