“…' Gibbons (1960); Coppen & Shaw (1963); Hullin, Swinscoe, McDonald & Dransfield (1968) and Aronoff, Evens & Durrel (1971) reported that sodium excretion increased following the commencement of lithium treatment. Baer, Kassir & Fieve (1970) ;Ho, Gershon & Pinckney (1970); and Birch & Jenner (1973) found that chronic administration of lithium to rats results in a significant decrease in brain sodium concentration. An increase in serum magnesium concentration has also been observed to accompany treatment with lithium (Nielsen, 1964;Aronoff et al (1971); and Andreoli, Villani & Brambilla, 1972;Mellerup, Plenge & Rafaelsen, 1973;and Birch & Jenner, 1973).…”