Thread by @NephRodby

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil Quick tutorial on oral urea. Urea is used for hypoNa bc urea excretion requires H20 excretion (without Na) and thus ⬆️ electrolyte free water clearance (EFWC) which ⬆️ [PNa] in pts with ⬇️ EFWC (most commonly SIADH).

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 2) Urea has a molecular weight of 60 (60 gram/mole = 1000 millimoles and urea has no charge so that is 1000 milli-osmoles/mole (mosm/mole)). The commercial products are sold as 15gm units (1/4 of a mole) = 250 mosm.

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 3) The average pt excretes ~750 mosm/day so adding 250 mosm allows third more of water intake/d, 30 gm 2/3 increase, and at 45 gm pt can double water intake.

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 4) Urea is used mostly for SIADH, to increase allowable water intake/day chronically or to raise [PNa] acutely. The other approach to increasing EFWC is to use an ADH antagonist eg tolvaptan but that is $$$ and as such hard to get approved as out-pt.

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 5) Urea can also be used for pts with poor solute intake “tea and toast hypoNa”, if they simply cannot increase their daily solute excretion (protein and Na).

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 6) Urea for this has been around for a long time but more recently 2 commercial flavored urea products have become available OTC marketed for hypoNa: #ureNa and #UreaAide

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 7) #ureNa was the first product (ure-Na.com) and was produced with a citrus flavor. Here I am testing it in 2017.

https://twitter.com/NephRodby/status/889225627135610880?s=20

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 8) I then bought chemical grade urea (Amazon) and mixed it with Crystal Light for less expensive version of #ure-Na. Except for using too much Crystal light (so sour), it was fine.

https://twitter.com/NephRodby/status/1139575669233541123?s=20

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 9) #UreaAide followed in 2020 (KidneyAide.com) but was sweet and minty. I tested it with the whole renal consult team, and the majority of those gave it a thumbs up. I proposed a #UreaAideChallenge”. I’m glad to see others joining.

https://twitter.com/NephRodby/status/1337149497793769476?s=20

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 10) Now #UreaAide is coming out with an unflavored bulk version (<1/2 the $) that they suggest you mix with Gatorade powder! The #UreaAideChallenge2 ?

@KidneyAide @sbABetterLeader @AnnaGaddy @IUKidney @hswapnil 11) @NephroMD is the USA #UreaCzar and has published a lot of his own urea for hypoNa research experience. I am an advocate as much bc of the physiology and fun math, but also bc it really works. Many hospital pharmacies will stock these and put on formulary, even if OTC.