Preparations and Doses.
1. Carbonate (lithii carbonas), 3 to 15 °Tains.
Citrate (lithii citras), 10 to 30 (=rains.
Effervescent citrate (lithii citras effervescens), 1 to 2 drachms.
2. Benzoate (lithii benzoas), 10 to 30 (*rains. t, Bromide (lithii broraidum), 5 to =10
Salicylate (lithii salicylas), 10 to 30 grains.
[The preparations in the first groups act as lithittin; those of thc second group have the action of the acid or element forming them.] Physiological Action.-13inet has shown that lithium salts give rise in ani mats to the followinff, series of symptoms: Weakness. diarrluva, nausea, dyspna, fall of temperature, convulsions, and death. The latter is attributed to de pression aml final arrest of thc heart in diastole, coupled with an inhibitory in fluence npon the respiratory centres. The peripheral nervous system is paralyzed and muscular excitability is reduced. The lithium salts probably have an important influence upon metabolism. They are promptly absorbed and elimi nated with the urine, which is rendered alkaline. They have been shown capable of dissolving uric acid a_nd the urates, and are therefore extensively used to coun teract the so-called uric-acid diathesis.
Lithium is excreted in the saliva, into t lie stomaelt and bowel, and in the urine. The greater amount is excreted in the urine, though more appears in the stom ach and bowel when nausea, vomiting, and diarrhcea have been profuse. It can
usually be demonstrated in the secre tions within ten minutes after a hypo dermic injection, though its excretion proceeds slowly, for the writer has found it in secretions twenty-three days after the injections Nvere stopped.
Lithium salts given to animals, hypo dermically or by the stomach, cause, sooner or later, fatal gastro-enteritis. This gastro-enteritis is, undoubtedly, connected with the excretion of the metal through the bowel-wall. These salts do not possess any diuretic action that cannot be accounted for by their salt action. They render the urine alka line, and thus act like the other alkalies. Lithium carbonate, in 15- to 20-grain to 17, grammes) doses, and lithia tablets have been known to cause gastro-intestinal symptoms in man. Di lute solutions of lithium salts are not solvents for uric acid or itrates. Clar ence .A. (Iood (Amer. Jour. Med. Sci ences. Feb.. 1003).
Therapenti cs.—The preparations of lithium have held a high reputation for efficiency in the treatment of the uric acid diathesis in its many phases. It has been claimed that they can dissolve uric acid calculi in the urinary passages or in the bladder. Haig has called our atten tion, however, to the fact that, although lithia forms salts with uric acid in the test-tube, in the body it has a greater affinity for the acid sodium phosphate in the blood, and thus the uric acid is left uncombined.