There's a fantastic Harold Klawans story about cupping. He was a senior neurologist, and his hospital contacted him to try to work out what was going wrong with a delerious older gent who would only speak in Yiddish, who presented with a fever and a really odd rash over his leg. They'd tried every other medical specialist they could think of, and had been through every possible diagnosis from ringworm to eczema on the leg rash. This had gone on for a week and he was steadily worsening. They thought it must have been some sort of exotic virus and were incredibly worried it was contagious.
Klawans realised that the old man had an infection in his leg, which had got so bad that he'd become delerious. And the leg rash? It was several lesions, some apparenly older than others, but all perfectly circular... The old guy had had a sore leg, and so been treating himself using traditional cupping. A course of fairly strong antibiotics and he remembered how to speak English and was fine.
If anyone ever suggests cupping, my advice is don't. I got talked into allowing a Chinese masseur to 'cup' me. Took two weeks for the bruises to heal...