Calc. sulph. is closely related to Hepar sulph. calc., which is an impure sulphide of calcium, but has a wider sphere and deeper action in suppurative processes. It is Schüssler's "Connective-tissue salt," and most of the indications for its use are derived from his clinical experience. In the last edition of his Biochemic Therapy Schüssler discards Calc. sul. because it is not an actual constituent of the tissues, and he distributes its functions between Silicea and Nat. Phos. Homoeopaths, having no Biochemic theory to support, may continue its use without scruple, especially as it has been proved by Hering and others. It is indicated in all kinds of cases after pus has found a vent. Nash has cured a case of suppurating kidney with it. It differs from Hepar in sensitiveness to air: Hepar cannot bear the slightest exposure; Calc. sul. has > in open air; better walking in it; desire for it. Both have < from change of weather. Calc. sul. has not the excessive sensitiveness to touch found in Hepar. Hansen recommends it in dry eczema in children. Cystic tumours, fibromata and polypi have been cured with Calc. sul.