Narrated AbdulAziz ibn Umar ibn AbdulAziz:

Some people of the deputation which came to my father reported the Messenger of Allah ﷺ as saying: Any physician who practises medicine when he was not known as a practitioner before that and he harms (the patients) he will be held responsible. AbdulAziz said: Here physician does not refer to a man by qualification. it means opening a vein, incision and cauterisation.

حَدَّثَنَا مُحَمَّدُ بْنُ الْعَلاَءِ، حَدَّثَنَا حَفْصٌ، حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ عُمَرَ بْنِ عَبْدِ الْعَزِيزِ، حَدَّثَنِي بَعْضُ الْوَفْدِ الَّذِينَ، قَدِمُوا عَلَى أَبِي قَالَ قَالَ رَسُولُ اللَّهِ ﷺ
" أَيُّمَا طَبِيبٍ تَطَبَّبَ عَلَى قَوْمٍ لاَ يُعْرَفُ لَهُ تَطَبُّبٌ قَبْلَ ذَلِكَ فَأَعْنَتَ فَهُوَ ضَامِنٌ " . قَالَ عَبْدُ الْعَزِيزِ أَمَا إِنَّهُ لَيْسَ بِالنَّعْتِ إِنَّمَا هُوَ قَطْعُ الْعُرُوقِ وَالْبَطُّ وَالْكَىُّ .