Relief of Fever, Minor Swelling, and Colds Ferrum Phos. (Ferrum Phosphoricum), the oxygen-carrier cell salt, offers a gentle, natural way to relieve minor fever and redness symptoms whether they are caused by the common cold, heat exposure or minor irritations. Ferrum Phos. is an effective remedy for minor swelling of the hands and is also ideal for relief from colds, particularly in the early phases of cold symptoms when throats get sore and start to swell, minor fevers cause chilliness and flushed faces, noses run, and dry coughs set in or begin to rattle in the chest, especially at night. Tablets are flavorless and dissolve immediately without water for no upset stomach.