Janos Rado: Desmopressin may counteract poliuria in lithium-induced nephrogenic diabetes insipidus

(Review of the literature)

Robert H. Belmaker’s comments

            Thank you for asking me to comment on this learned and mechanistically sophisticated piece by Janos Radó. I certainly agree that we must find treatments for lithium side effects so that fewer patients feel that they have to stop lithium. However, Radó does not give a biochemical explanation of lithium-induced nephrogenic diabetes insipidus and whether it is so clear that it is related to genetic forms. His data is basically one case of desmopressin-treated lithium-induced diabetes insipidus.  Radó points out that the older literature assumed a lower maximum dose for desmopressin; now desmopressin is given in much, much higher doses for its effect on clotting.  However, therein exactly lies the rub:  the molecule has effects on physiology other than on the kidney, especially at high doses.  That is justified for a severe clotting disorder. But we really do not know whether these clotting effects and others not yet known of high dose desmopressin are justified if the high doses were to be given widely for lithium-induced nocturia. 

November 21, 2019