Sure they did. I remember having to go to VPCL’s pharmacy to pick up what the vet had compounded. No it wasn’t Omeprazole, but it was ulcer meds. Ranitidine? Famotidine? Can’t remember at this late date - one of the oldie but goodies. Had to administer about a billion times it day it felt like.
The particular episode I’m remembering was for a yearling that kept purposefully casting himself. He was in a bad way and got fixed right up. The lip flapper was a hard keeper owned by someone else and their vet didn’t put the symptoms all together because they weren’t so obvious. A couple of years later, another lip flapper belonging to another owner was diagnosed and treated by the same vet that dealt with the yearling.
The one vet dealt with a LOT of TBs and STBDs and we were lucky as heck to have him work on our riding horses. The other vet was with a general practice (large and small) with no really solid equine specialists in the practice.