Sunan Abi Dawud 3861 Hasan (Al-Albani)
قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَنِ احْتَجَمَ لِسَبْعَ عَشْرَةَ وَتِسْعَ عَشْرَةَ وَإِحْدَى وَعِشْرِينَ كَانَ شِفَاءً مِنْ كُلِّ دَاءٍ .
— Narrated by Abu Huraira from the Prophet ﷺ
“Whoever has himself cupped on the 17th, the 19th, and the 21st (of the lunar month), it will be a remedy for every disease.”