I found this story on Futility Closet’s blog here.
“Secessionist Roger A. Pryor was visiting Fort Sumter just before the outbreak of the Civil War when he accidentally drank a bottle of poison. A Union doctor named Samuel Crawford pumped his stomach, saving his life.
“‘Some of us questioned the doctor’s right to interpose in a case of this kind,’ wrote Union captain Abner Doubleday. ‘It was argued that if any rebel leader chose to come over to Fort Sumter and poison himself, the Medical Department had no business to interfere with such a laudable intention.’
“‘The doctor, however, claimed, with some show of reason, that he himself was held responsible to the United States for the medicine in the hospital, and therefore he could not permit Pryor to carry any of it away.’