With regard to the therapeutical use of iron waters, formerly invoked so constantly whenever "strengthening" was desired, we must note that more discrimination is now exercised. Sea-bathing, mountain air, quinine, nux vomica, and other remedies are more used, and iron is ordered more exclusively for true anaemia and chlorosis. Modern medicine, however, recognizes anaemia arising from fever, pneumonia, and most acute disorders quite as distinctly as from hemorrhage (cf. Coupland: "Gulstonian Lectures," March, 1881). The more rapidly it is produced, and the more directly from loss of blood, or of component parts of blood, as in hemorrhage, exudation, or suppuration, the greater the indication for iron in full doses: indeed, officinal preparations are often better in such cases, and chalybeate waters find their use only in later stages.

Their advantages are that they contain a compound (generally a bicarbonate) which is readily digested by the stomach, since it is easily changed into lactate or chloride; that this is well diluted, and so more readily absorbed; and that the free carbonic acid given at the same time is a useful stimulant to the gastro-intestinal membrane. On the other hand, these conditions, under certain circumstances, may be disadvantageous, and a full dose of more concentrated preparations will give better results: for instance, symptoms of congestion of the head or chest, under a course of carbonated chalybeate, are referred by many physicians to the carbonic acid rather than to the iron, and in such cases an ordinary pharmaceutical preparation may agree better (Braun).

Simple (true) chlorosis, occurring during the developmental period, seems connected with direct loss of iron, which sometimes manifests itself by an increase in the amount passed in the urine (Braun); and it is in this form of anaemia that the administration of iron proves most successful. It is seen among the poorer or the middle classes more frequently than among the higher, in whom chlorosis is often complicated with mental excitement or depression, hysteria, leucorrhoea, etc.

The more indirect the anaemia - when arising, for instance, from impaired general nutrition, with deficiency of albumen and fibrine rather than of blood-cells, or from special derangement of organs or nerves - the slower and the more uncertain is the effect of iron; the anaemia of malnutrition is often better treated by nourishment and hygiene, while the former connected, e.g., with hysteria, may be aggravated by iron internally, but relieved by indifferent baths as at Schlangenbad.

Anaemia complicated with or dependent on chronic discharges, such as from caries of bones, diarrhoea, catarrh, etc., is a generally impaired condition of the blood, and should be also treated dietetically, by meat, fat, milk, and with due attention to hygiene. The anaemia of prolonged lactation, which is often accompanied by dyspepsia, requires preliminary medical treatment - weaning the infant being naturally the first indication. In amenorrhoea and other disorders of menstruation, the indication for iron is the degree of anaemia. We should endeavor to put the blood in such a condition that nature can secure from it a healthy result.

Sometimes a salt water (such as Kissingen) and careful hygiene will give better results than iron, while in other cases a compound somewhat purgative iron spring, as at Franzensbad, will be more beneficial. Generally speaking, constipation in these cases requires purgative sulphated or saline waters, while if dyspepsia or diarrhoea be present, they must be combated by appropriate treatment.

Atony of the stomach and intestinal canal is often benefited by a course of iron waters, and the accompanying carbonic acid becomes also valuable in this disorder, which frequently complicates chlorosis and anaemia.

Certain neuroses are also much relieved by chalybeates, but the main indication for their use is the presence of anaemia.

Most iron springs are cold, but are much better borne by chlorotic girls if warmed by the addition of hot water or whey.