Al-Kāfi - Volume 6 > The Saltwort and Cyperus
Hadith #6

عَنْهُ عَنِ ابْنِ مَحْبُوبٍ عَنْ أَبِي وَلَّادٍ قَالَ رَأَيْتُ أَبَا الْحَسَنِ الْأَوَّلَ ( عليه السلام ) فِي الْحِجْرِ وَ هُوَ قَاعِدٌ وَ مَعَهُ عِدَّةٌ مِنْ أَهْلِ بَيْتِهِ فَسَمِعْتُهُ يَقُولُ ضُرِبَتْ عَلَيَّ أَسْنَانِي فَأَخَذْتُ السُّعْدَ فَدَلَكْتُ بِهِ أَسْنَانِي فَنَفَعَنِي ذَلِكَ وَ سَكَنَتْ عَنِّي .

6. It is narrated from the narrator of the previous Hadith from ibn Mahbub from abu Wallad who has said the following: “I once saw abu al-Hassan sitting in al-Hijr (near al-Ka‘bah) along with a group of his family members and I heard him saying, ‘I had a toothache so I took cyperus and rubbed with it my teeth, it benefited me and the pain calmed down.’” End of the Book of Foods followed by the Book of Drinks, by the will of Allah, and all praise belongs to Allah alone, O Allah, grant compensation to Muhammad and his family worthy of their services to Your cause."