الحناء
A plant dye applied to hair and skin, mentioned in reports about grooming practice and discussed by commentators for minor topical complaints.
مَا مِنْ دَاءٍ إِلَّا وَالْحِنَّاءُ لَهُ دَوَاءٌ
“There is scarcely an ailment for which henna does not offer some remedy.” (meaning, not a literal translation)
Ibn al-Qayyim and al-Dhahabi both describe henna's cooling, astringent quality — traditionally applied to minor burns, cracked skin, and as a hair conditioner and dye.