Dhakwan Abu Salah al-Saman al-Ziyat ذكوان أبو صالح السمان الزيات · Chapters on Medicine

"The Messenger of Allah (s.a.w) forbade from cures that are Khabith." Meaning poison

"When one of you suffers from fever - and indeed fever is a piece of the Fire - let him extinguish it with water. Let him stand in a flowing river facing the direction of it and say: Allahummashfi 'abdaka wa saddik Rasulak ('In the name off Allah. O Allah! Cure your slave and testify to Your Messenger.)' Doing so after Salat As-Subh(Fajr) and before the rising of the sun. Let him submerse himself in it three times, for three…

"When one of you visits the ill, then reassure him regarding his lifespan. Indeed that will not repel anything, but it will comfort his soul."