The Messenger of Allah ﷺ said, "Whoever practices medicine without being known for any expertise in it is liable."Nasr said, "Ibn Jurayj narrated this to me."
حدثنا نصر بن عاصم الأنطاكي ومحمد بن الصباح بن سفيان أن الوليد بن مسلم أخبرهم عن ابن جريج
أن رسول الله ﷺ قال من تطبب ولا يعلم منه طب فهو ضامن قال نصر قال حدثني ابن جريج
[Its isnad is daif]. Ibn Majah, in the Book of Medicine, chapter "Whoever practices medicine without having knowledge of it," hadith 3466, and Nasai, hadith 4834, both narrated it from the hadith of Walid bin Muslim via the same route. Ibn Jurayj used the ambiguous form of transmission (anana), and the hadith has a corroborating witness that is also daif.