Found the title.
Madhouse: a tale of megalomania and modern medicine.
A true tale of a doc tire who believed mental illnesses was caused by infections and how he pulled teeth as a precaution. It's not BP specifically but it details anougher barbaric treatment fostered on the mentality I'll in the name of modern meds, much as the lobotomy was in its day.

I too picked the unquiet mind because I already have a copy.