It was narrated from ‘Amr bin Shu’aib, from his father, that his grandfather said:
“The Messenger of Allah ﷺ said: ‘Whoever gives medical treatment, with no prior knowledge of medicine, is responsible (for any harm done).’”

حَدَّثَنَا هِشَامُ بْنُ عَمَّارٍ، وَرَاشِدُ بْنُ سَعِيدٍ الرَّمْلِيُّ، قَالاَ حَدَّثَنَا الْوَلِيدُ بْنُ مُسْلِمٍ، حَدَّثَنَا ابْنُ جُرَيْجٍ، عَنْ عَمْرِو بْنِ شُعَيْبٍ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، قَالَ قَالَ رَسُولُ اللَّهِ ﷺ " مَنْ تَطَبَّبَ وَلَمْ يُعْلَمْ مِنْهُ طِبٌّ قَبْلَ ذَلِكَ فَهُوَ ضَامِنٌ " .