Old English carian, cearian be anxious, grieve; to feel concern or interest, from Proto-Germanic *karojanan (cf. Old High German charon to lament, Old Saxon karon to care, to sorrow), from the same source as care (n.).
Epsom salt is used as bath salts and for isolation tanks. Magnesium sulfate is the main preparation of intravenous magnesium. Internal uses include: Oral magnesium sulfate is commonly used as a saline laxative or osmotic purgative.
Epsom Salt Council: About Epsom Salt, Soaking, Frequently Asked Questions. Rosemary H. Waring, PhD, DSc, School of Biosciences, University of Birmingham, England. Taz Bhatia, MD, director, The Atlanta Center for Holistic and Integrative Medicine, Atlanta, GA.