mercurius sulphuricus
Hydrothorax, if occurring from heart or liver diseases; dyspnoea, has to sit, cannot lie down. Extremities swollen; stool loose, watery, causing severe burning and soreness; burning in chest. "When it acts well it produces a profuse, watery diarrhoea with great relief to the patient; it is as important as Arsenicum in hydrothorax" - Lippe.