**Pasquale Esposito \*, Novella Evelina Conti, Valeria Falqui, Leda Cipriani, Daniela Picciotto, Francesca Costigliolo, Giacomo Garibotto, Michela Saio and Francesca Viazzi**

Clinica Nefrologica, Dialisi, Trapianto, Department of Internal Medicine, University of Genoa and IRCCS Ospedale Policlinico San Martino, Viale Benedetto XV, 16132 Genoa, Italy; novella.conti@hsanmartino.it (N.E.C.); valeria.falqui@hsanmartino.it (V.F.); cipriani.leda@gmail.com (L.C.); danipicciotto@me.com (D.P.); 3232594@studenti.unige.it (F.C.); gari@unige.it (G.G.); michela.saio@virgilio.it (M.S.); francesca.viazzi@unige.it (F.V.)

**\*** Correspondence: pasqualeesposito@hotmail.com; Tel.: +39-0105-5553-62

Received: 3 June 2020; Accepted: 21 July 2020; Published: 22 July 2020

**Abstract:** Hyperkalemia may cause life-threatening cardiac and neuromuscular alterations, and it is associated with high mortality rates. Its treatment includes a multifaceted approach, guided by potassium levels and clinical presentation. In general, treatment of hyperkalemia may be directed towards stabilizing cell membrane potential, promoting transcellular potassium shift and lowering total K<sup>+</sup> body content. The latter can be obtained by dialysis, or by increasing potassium elimination by urine or the gastrointestinal tract. Until recently, the only therapeutic option for increasing fecal K<sup>+</sup> excretion was represented by the cation-exchanging resin sodium polystyrene sulfonate. However, despite its common use, the efficacy of this drug has been poorly studied in controlled studies, and concerns about its safety have been reported. Interestingly, new drugs, namely patiromer and sodium zirconium cyclosilicate, have been developed to treat hyperkalemia by increasing gastrointestinal potassium elimination. These medications have proved their efficacy and safety in large clinical trials, involving subjects at high risk of hyperkalemia, such as patients with heart failure and chronic kidney disease. In this review, we discuss the mechanisms of action and the updated data of patiromer and sodium zirconium cyclosilicate, considering that the availability of these new treatment options offers the possibility of improving the management of both acute and chronic hyperkalemia.

**Keywords:** hyperkalemia; chronic kidney disease; heart failure; sodium polystyrene sulfonate; patiromer; sodium zirconium cyclosilicate
