Mishkat al-Masabih 4545

‘Abd ar-Rahman b. ‘Uthman told that when a physician consulted the Prophet (ﷺ) about putting frogs in medicine he forbade him to kill them.*
Abu Dawud transmitted it.
* The flesh of frogs mixed with olive oil was used as an antidote for snake bite, and the fat was considered helpful for extracting teeth. The prohibition of killing frogs most probably applies only to killing them for medicinal purposes.