User login
Q)I have heard talk about the development of new drugs to treat hyperkalemia. What is the status of these?
Hyperkalemia is a commonly seen electrolyte imbalance in clinical practice. Risks associated with moderate-to-severe hyperkalemia include potentially fatal cardiac conduction abnormalities/arrhythmias, making identification and management critical. An in-depth discussion of hyperkalemia diagnosis can be found in our March 2017 CE/CME activity (2017;27[3]:40-49).
Risk factors for hyperkalemia include excess intake or supplementation of potassium, type 2 diabetes, liver cirrhosis, congestive heart failure (CHF), and chronic kidney disease (CKD). The kidneys excrete 90% to 95% of ingested potassium, and the gut excretes the rest. Normal kidneys take six to 12 hours to excrete an acute potassium load. As kidney function decreases, risk for hyperkalemia increases.1 Hyperkalemia rates as high as 26% have been observed in patients with CKD stages 3 to 5 (glomerular filtration rate [GFR], < 60 mL/min).2
Renin-angiotensin-aldosterone system (RAAS) inhibitors—including ACE inhibitors (ACEis), angiotensin-receptor blockers, and aldosterone agonists—are associated with hyperkalemia. While RAAS therapy can play an important role in the management of CKD and cardiovascular disease (CVD), the development of hyperkalemia can necessitate a dose reduction or discontinuation of these medications, limiting their therapeutic benefit. Other medications that elevate risk for hyperkalemia include NSAIDs, heparin, cyclosporine, amiloride, triamterene, and nonselective ß-blockers.1
Therapeutic options for nonurgent treatment of hyperkalemia are limited. In addition to reducing or discontinuing associated medications, strategies include use of diuretics (as appropriate), treatment of metabolic acidosis, and dietary restrictions (ie, limiting high-potassium foods).1 Pharmacologically, there has been one (less than ideal) option—until recently.
Sodium polystyrene sulfonate (SPS), an ion-exchange resin approved in 1958, can be used to treat hyperkalemia.3 It comes in an enema and an oral form; the former has a faster onset, but the latter is more effective, with an onset of action of one to two hours and a duration of four to six hours.1 However, each gram of SPS contains 100 g of sodium, and the typical dose of SPS is 15 g to 60 g.4 The resulting increase in sodium load can be a concern for patients with CHF, severe hypertension, or severe edema.5
Data from randomized controlled trials (RCTs) are limited; however, one double-blind RCT investigated the effect of SPS on 33 patients with CKD and mild-to-moderate hyperkalemia (potassium level, 5 mEq/L to 5.9 mEq/L). The researchers found that patients who took 30 g/d of SPS for seven days experienced a 73% reduction in serum potassium, compared with a 38% reduction in patients who took a placebo. Of note, more gastrointestinal issues were observed in the SPS group.6
Additionally, a retrospective chart review of 14 patients with CKD and heart disease found low-dose SPS to be safe and effective when used as a secondary measure for hyperkalemia prevention in those taking RAAS therapy.7 However, a systematic review found that SPS use with and without concurrent sorbitol may be associated with serious and fatal gastrointestinal injuries.8 In 2011, the FDA issued a black box warning regarding increased risk for intestinal necrosis when SPS is used with sorbitol.9 In 2015, the FDA recommended separating SPS from other oral medications by at least six hours, due to its potential to bind with other medications.10
Patiromer, a new potassium binder, was approved by the FDA in 2015. This sodium-free, nonabsorbed, spherical polymer uses calcium as the exchange cation to bind potassium in the gastrointestinal tract. Its onset of action is seven hours, with a 24-hour duration of action. It is not approved for emergency use. There are no renal dosing adjustment considerations with patiromer.
In RCTs, patiromer has been associated with a significant reduction in serum potassium in patients with CKD (with or without diabetes) taking RAAS therapy. The starting dose is 8.4 g/d mixed with water, taken with food; this can be increased by 8.4 g each week as needed, to a maximum dosage of 25.2 g/d. Patiromer binds between 8.5 mEq to 8.8 mEq of potassium per gram of polymer.
The original approval included a black box warning to take patiromer six hours before and after other medications, due to concern for binding with certain medications. However, after an additional study in 2016, the FDA removed this warning and approved a change in administration to three hours before and after taking other medications.
Use of patiromer is not advised in those with severe constipation, bowel obstruction/impaction, or allergies to any of its components.11 Adverse reactions associated with patiromer include constipation (which generally improves with time), hypomagnesemia, diarrhea, nausea, abdominal discomfort, and flatulence. A 52-week RCT of 304 patients with CKD on RAAS found the most common adverse event to be mild-to-moderate constipation (6.3% of patients), with two patients discontinuing therapy as a result.4 In clinical trials, 9% of patients developed hypomagnesemia (serum magnesium value, < 1.4 mg/dL). It is recommended that serum magnesium levels be monitored and supplementation offered, when appropriate.11
Sodium zirconium cyclosilicate (ZS-9) is among the potassium-lowering medications on the horizon. In 2016, the FDA accepted a new drug application for this insoluble, unabsorbed cation exchanger that also works in the GI tract and uses sodium and hydrogen as exchange cations.12
For now, however, dietary education remains a mainstay of treatment for patients with elevated serum potassium levels. It is particularly important to inform your patients that many salt substitutes and low-sodium products contain potassium chloride. They should therefore exercise caution when incorporating sodium-reducing components into their diet. —CS
Cynthia Smith, DNP, CNN-NP, APRN, FNP-BC
Renal Consultants, PLLC, South Charleston, West Virginia
1. Gilbert S, Weiner D, Gipson D, eds; National Kidney Foundation. Primer on Kidney Diseases. 6th ed. Philadelphia, PA: Saunders Elsevier; 2014.
2. Einhorn LM, Zhan M, Hsu VD, et al. The frequency of hyperkalemia and its significance in chronic kidney disease. Arch Intern Med. 2009;169(12):1156-1162.
3. Flinn RB, Merrill JP, Welzant WR. Treatment of the oliguric patient with a new sodium-exchange resin and sorbitol: a preliminary report. N Engl J Med. 1961;264:111-115.
4. Dunn JD, Benton WW, Orozco-Torrentera E, Adamson RT. The burden of hyperkalemia in patients with cardiovascular and renal disease. Am J Manag Care. 2015;21(15 suppl): s307-s315.
5. Li L, Harrison SD, Cope MJ, et al. Mechanism of action and pharmacology of patiromer, a nonabsorbed cross-linked polymer that lowers serum potassium concentration in patients with hyperkalemia. J Cardiovasc Pharmacol Ther. 2016;21(5):456-465.
6. Lepage L, Dufour AC, Doiron J, et al. Randomized clinical trial of sodium polystyrene sulfonate for the treatment of mild hyperkalemia in CKD. Clin J Am Soc Nephrol. 2015; 10(12):2136-2142.
7. Chernin G, Gal-Oz A, Ben-Assa E, et al. Secondary prevention of hyperkalemia with sodium polystyrene sulfonate in cardiac and kidney patients on renin-angiotensin-aldosterone system inhibition therapy. Clin Cardiol. 2012;35(1):32-36.
8. Harel Z, Harel S, Shah PS, et al. Gastrointestinal adverse events with sodium polystyrene sulfonate (Kayexalate) use: a systematic review. Am J Med. 2013;126(3):264.e9-e24.
9. FDA. Safety warning: Kayexalate (sodium polystyrene sulfonate) powder. www.fda.gov/Safety/MedWatch/SafetyInformation/ucm186845.htm. Accessed February 15, 2017.
10. FDA. FDA drug safety communication: FDA required drug interaction studies with potassium-lowering drug Kayexalate (sodium polystyrene sulfonate). www.fda.gov/Drugs/DrugSafety/ucm468035.htm. Accessed March 1, 2017.
11. Veltassa® (patiromer) [package insert]. Redwood City, CA: Relypsa, Inc; 2016. www.veltassa.com/pi.pdf. Accessed March 1, 2017.
12. AstraZeneca. FDA accepts for review New Drug Application for sodium zirconium cyclosilicate (ZS-9) for the treatment of hyperkalaemia. www.astrazeneca.com/investor-relations/Stock-exchange-announcements/fda-accepts-for-review-new-drug-application-for-sodium-zirconium-18102016.html. Accessed March 1, 2017.
Clinician Reviews in partnership with
Renal Consult is edited by Jane S. Davis, CRNP, DNP, a member of the Clinician Reviews editorial board, who is a nurse practitioner in the Division of Nephrology at the University of Alabama at Birmingham and is the communications chairperson for the National Kidney Foundation’s Council of Advanced Practitioners (NKF-CAP); and Kim Zuber, PA-C, MSPS, DFAAPA, a semi-retired PA who works with the American Academy of Nephrology PAs and is a past chair of the NKF-CAP. This month’s responses were authored by Cynthia Smith, DNP, CNN-NP, APRN, FNP-BC, who practices at Renal Consultants, PLLC, in South Charleston, West Virginia, Rebecca V. Rokosky, MSN, APRN, FNP-BC, who is Sub Investigator in the Clinical Advancement Center, PPLC, in San Antonio, Texas, and Shannon M. Rice, MS, PA-C, who is in the Division of Nephrology and Hypertension, Department of Medicine, at the University of California, San Diego.
Clinician Reviews in partnership with
Renal Consult is edited by Jane S. Davis, CRNP, DNP, a member of the Clinician Reviews editorial board, who is a nurse practitioner in the Division of Nephrology at the University of Alabama at Birmingham and is the communications chairperson for the National Kidney Foundation’s Council of Advanced Practitioners (NKF-CAP); and Kim Zuber, PA-C, MSPS, DFAAPA, a semi-retired PA who works with the American Academy of Nephrology PAs and is a past chair of the NKF-CAP. This month’s responses were authored by Cynthia Smith, DNP, CNN-NP, APRN, FNP-BC, who practices at Renal Consultants, PLLC, in South Charleston, West Virginia, Rebecca V. Rokosky, MSN, APRN, FNP-BC, who is Sub Investigator in the Clinical Advancement Center, PPLC, in San Antonio, Texas, and Shannon M. Rice, MS, PA-C, who is in the Division of Nephrology and Hypertension, Department of Medicine, at the University of California, San Diego.
Clinician Reviews in partnership with
Renal Consult is edited by Jane S. Davis, CRNP, DNP, a member of the Clinician Reviews editorial board, who is a nurse practitioner in the Division of Nephrology at the University of Alabama at Birmingham and is the communications chairperson for the National Kidney Foundation’s Council of Advanced Practitioners (NKF-CAP); and Kim Zuber, PA-C, MSPS, DFAAPA, a semi-retired PA who works with the American Academy of Nephrology PAs and is a past chair of the NKF-CAP. This month’s responses were authored by Cynthia Smith, DNP, CNN-NP, APRN, FNP-BC, who practices at Renal Consultants, PLLC, in South Charleston, West Virginia, Rebecca V. Rokosky, MSN, APRN, FNP-BC, who is Sub Investigator in the Clinical Advancement Center, PPLC, in San Antonio, Texas, and Shannon M. Rice, MS, PA-C, who is in the Division of Nephrology and Hypertension, Department of Medicine, at the University of California, San Diego.
Q)I have heard talk about the development of new drugs to treat hyperkalemia. What is the status of these?
Hyperkalemia is a commonly seen electrolyte imbalance in clinical practice. Risks associated with moderate-to-severe hyperkalemia include potentially fatal cardiac conduction abnormalities/arrhythmias, making identification and management critical. An in-depth discussion of hyperkalemia diagnosis can be found in our March 2017 CE/CME activity (2017;27[3]:40-49).
Risk factors for hyperkalemia include excess intake or supplementation of potassium, type 2 diabetes, liver cirrhosis, congestive heart failure (CHF), and chronic kidney disease (CKD). The kidneys excrete 90% to 95% of ingested potassium, and the gut excretes the rest. Normal kidneys take six to 12 hours to excrete an acute potassium load. As kidney function decreases, risk for hyperkalemia increases.1 Hyperkalemia rates as high as 26% have been observed in patients with CKD stages 3 to 5 (glomerular filtration rate [GFR], < 60 mL/min).2
Renin-angiotensin-aldosterone system (RAAS) inhibitors—including ACE inhibitors (ACEis), angiotensin-receptor blockers, and aldosterone agonists—are associated with hyperkalemia. While RAAS therapy can play an important role in the management of CKD and cardiovascular disease (CVD), the development of hyperkalemia can necessitate a dose reduction or discontinuation of these medications, limiting their therapeutic benefit. Other medications that elevate risk for hyperkalemia include NSAIDs, heparin, cyclosporine, amiloride, triamterene, and nonselective ß-blockers.1
Therapeutic options for nonurgent treatment of hyperkalemia are limited. In addition to reducing or discontinuing associated medications, strategies include use of diuretics (as appropriate), treatment of metabolic acidosis, and dietary restrictions (ie, limiting high-potassium foods).1 Pharmacologically, there has been one (less than ideal) option—until recently.
Sodium polystyrene sulfonate (SPS), an ion-exchange resin approved in 1958, can be used to treat hyperkalemia.3 It comes in an enema and an oral form; the former has a faster onset, but the latter is more effective, with an onset of action of one to two hours and a duration of four to six hours.1 However, each gram of SPS contains 100 g of sodium, and the typical dose of SPS is 15 g to 60 g.4 The resulting increase in sodium load can be a concern for patients with CHF, severe hypertension, or severe edema.5
Data from randomized controlled trials (RCTs) are limited; however, one double-blind RCT investigated the effect of SPS on 33 patients with CKD and mild-to-moderate hyperkalemia (potassium level, 5 mEq/L to 5.9 mEq/L). The researchers found that patients who took 30 g/d of SPS for seven days experienced a 73% reduction in serum potassium, compared with a 38% reduction in patients who took a placebo. Of note, more gastrointestinal issues were observed in the SPS group.6
Additionally, a retrospective chart review of 14 patients with CKD and heart disease found low-dose SPS to be safe and effective when used as a secondary measure for hyperkalemia prevention in those taking RAAS therapy.7 However, a systematic review found that SPS use with and without concurrent sorbitol may be associated with serious and fatal gastrointestinal injuries.8 In 2011, the FDA issued a black box warning regarding increased risk for intestinal necrosis when SPS is used with sorbitol.9 In 2015, the FDA recommended separating SPS from other oral medications by at least six hours, due to its potential to bind with other medications.10
Patiromer, a new potassium binder, was approved by the FDA in 2015. This sodium-free, nonabsorbed, spherical polymer uses calcium as the exchange cation to bind potassium in the gastrointestinal tract. Its onset of action is seven hours, with a 24-hour duration of action. It is not approved for emergency use. There are no renal dosing adjustment considerations with patiromer.
In RCTs, patiromer has been associated with a significant reduction in serum potassium in patients with CKD (with or without diabetes) taking RAAS therapy. The starting dose is 8.4 g/d mixed with water, taken with food; this can be increased by 8.4 g each week as needed, to a maximum dosage of 25.2 g/d. Patiromer binds between 8.5 mEq to 8.8 mEq of potassium per gram of polymer.
The original approval included a black box warning to take patiromer six hours before and after other medications, due to concern for binding with certain medications. However, after an additional study in 2016, the FDA removed this warning and approved a change in administration to three hours before and after taking other medications.
Use of patiromer is not advised in those with severe constipation, bowel obstruction/impaction, or allergies to any of its components.11 Adverse reactions associated with patiromer include constipation (which generally improves with time), hypomagnesemia, diarrhea, nausea, abdominal discomfort, and flatulence. A 52-week RCT of 304 patients with CKD on RAAS found the most common adverse event to be mild-to-moderate constipation (6.3% of patients), with two patients discontinuing therapy as a result.4 In clinical trials, 9% of patients developed hypomagnesemia (serum magnesium value, < 1.4 mg/dL). It is recommended that serum magnesium levels be monitored and supplementation offered, when appropriate.11
Sodium zirconium cyclosilicate (ZS-9) is among the potassium-lowering medications on the horizon. In 2016, the FDA accepted a new drug application for this insoluble, unabsorbed cation exchanger that also works in the GI tract and uses sodium and hydrogen as exchange cations.12
For now, however, dietary education remains a mainstay of treatment for patients with elevated serum potassium levels. It is particularly important to inform your patients that many salt substitutes and low-sodium products contain potassium chloride. They should therefore exercise caution when incorporating sodium-reducing components into their diet. —CS
Cynthia Smith, DNP, CNN-NP, APRN, FNP-BC
Renal Consultants, PLLC, South Charleston, West Virginia
Q)I have heard talk about the development of new drugs to treat hyperkalemia. What is the status of these?
Hyperkalemia is a commonly seen electrolyte imbalance in clinical practice. Risks associated with moderate-to-severe hyperkalemia include potentially fatal cardiac conduction abnormalities/arrhythmias, making identification and management critical. An in-depth discussion of hyperkalemia diagnosis can be found in our March 2017 CE/CME activity (2017;27[3]:40-49).
Risk factors for hyperkalemia include excess intake or supplementation of potassium, type 2 diabetes, liver cirrhosis, congestive heart failure (CHF), and chronic kidney disease (CKD). The kidneys excrete 90% to 95% of ingested potassium, and the gut excretes the rest. Normal kidneys take six to 12 hours to excrete an acute potassium load. As kidney function decreases, risk for hyperkalemia increases.1 Hyperkalemia rates as high as 26% have been observed in patients with CKD stages 3 to 5 (glomerular filtration rate [GFR], < 60 mL/min).2
Renin-angiotensin-aldosterone system (RAAS) inhibitors—including ACE inhibitors (ACEis), angiotensin-receptor blockers, and aldosterone agonists—are associated with hyperkalemia. While RAAS therapy can play an important role in the management of CKD and cardiovascular disease (CVD), the development of hyperkalemia can necessitate a dose reduction or discontinuation of these medications, limiting their therapeutic benefit. Other medications that elevate risk for hyperkalemia include NSAIDs, heparin, cyclosporine, amiloride, triamterene, and nonselective ß-blockers.1
Therapeutic options for nonurgent treatment of hyperkalemia are limited. In addition to reducing or discontinuing associated medications, strategies include use of diuretics (as appropriate), treatment of metabolic acidosis, and dietary restrictions (ie, limiting high-potassium foods).1 Pharmacologically, there has been one (less than ideal) option—until recently.
Sodium polystyrene sulfonate (SPS), an ion-exchange resin approved in 1958, can be used to treat hyperkalemia.3 It comes in an enema and an oral form; the former has a faster onset, but the latter is more effective, with an onset of action of one to two hours and a duration of four to six hours.1 However, each gram of SPS contains 100 g of sodium, and the typical dose of SPS is 15 g to 60 g.4 The resulting increase in sodium load can be a concern for patients with CHF, severe hypertension, or severe edema.5
Data from randomized controlled trials (RCTs) are limited; however, one double-blind RCT investigated the effect of SPS on 33 patients with CKD and mild-to-moderate hyperkalemia (potassium level, 5 mEq/L to 5.9 mEq/L). The researchers found that patients who took 30 g/d of SPS for seven days experienced a 73% reduction in serum potassium, compared with a 38% reduction in patients who took a placebo. Of note, more gastrointestinal issues were observed in the SPS group.6
Additionally, a retrospective chart review of 14 patients with CKD and heart disease found low-dose SPS to be safe and effective when used as a secondary measure for hyperkalemia prevention in those taking RAAS therapy.7 However, a systematic review found that SPS use with and without concurrent sorbitol may be associated with serious and fatal gastrointestinal injuries.8 In 2011, the FDA issued a black box warning regarding increased risk for intestinal necrosis when SPS is used with sorbitol.9 In 2015, the FDA recommended separating SPS from other oral medications by at least six hours, due to its potential to bind with other medications.10
Patiromer, a new potassium binder, was approved by the FDA in 2015. This sodium-free, nonabsorbed, spherical polymer uses calcium as the exchange cation to bind potassium in the gastrointestinal tract. Its onset of action is seven hours, with a 24-hour duration of action. It is not approved for emergency use. There are no renal dosing adjustment considerations with patiromer.
In RCTs, patiromer has been associated with a significant reduction in serum potassium in patients with CKD (with or without diabetes) taking RAAS therapy. The starting dose is 8.4 g/d mixed with water, taken with food; this can be increased by 8.4 g each week as needed, to a maximum dosage of 25.2 g/d. Patiromer binds between 8.5 mEq to 8.8 mEq of potassium per gram of polymer.
The original approval included a black box warning to take patiromer six hours before and after other medications, due to concern for binding with certain medications. However, after an additional study in 2016, the FDA removed this warning and approved a change in administration to three hours before and after taking other medications.
Use of patiromer is not advised in those with severe constipation, bowel obstruction/impaction, or allergies to any of its components.11 Adverse reactions associated with patiromer include constipation (which generally improves with time), hypomagnesemia, diarrhea, nausea, abdominal discomfort, and flatulence. A 52-week RCT of 304 patients with CKD on RAAS found the most common adverse event to be mild-to-moderate constipation (6.3% of patients), with two patients discontinuing therapy as a result.4 In clinical trials, 9% of patients developed hypomagnesemia (serum magnesium value, < 1.4 mg/dL). It is recommended that serum magnesium levels be monitored and supplementation offered, when appropriate.11
Sodium zirconium cyclosilicate (ZS-9) is among the potassium-lowering medications on the horizon. In 2016, the FDA accepted a new drug application for this insoluble, unabsorbed cation exchanger that also works in the GI tract and uses sodium and hydrogen as exchange cations.12
For now, however, dietary education remains a mainstay of treatment for patients with elevated serum potassium levels. It is particularly important to inform your patients that many salt substitutes and low-sodium products contain potassium chloride. They should therefore exercise caution when incorporating sodium-reducing components into their diet. —CS
Cynthia Smith, DNP, CNN-NP, APRN, FNP-BC
Renal Consultants, PLLC, South Charleston, West Virginia
1. Gilbert S, Weiner D, Gipson D, eds; National Kidney Foundation. Primer on Kidney Diseases. 6th ed. Philadelphia, PA: Saunders Elsevier; 2014.
2. Einhorn LM, Zhan M, Hsu VD, et al. The frequency of hyperkalemia and its significance in chronic kidney disease. Arch Intern Med. 2009;169(12):1156-1162.
3. Flinn RB, Merrill JP, Welzant WR. Treatment of the oliguric patient with a new sodium-exchange resin and sorbitol: a preliminary report. N Engl J Med. 1961;264:111-115.
4. Dunn JD, Benton WW, Orozco-Torrentera E, Adamson RT. The burden of hyperkalemia in patients with cardiovascular and renal disease. Am J Manag Care. 2015;21(15 suppl): s307-s315.
5. Li L, Harrison SD, Cope MJ, et al. Mechanism of action and pharmacology of patiromer, a nonabsorbed cross-linked polymer that lowers serum potassium concentration in patients with hyperkalemia. J Cardiovasc Pharmacol Ther. 2016;21(5):456-465.
6. Lepage L, Dufour AC, Doiron J, et al. Randomized clinical trial of sodium polystyrene sulfonate for the treatment of mild hyperkalemia in CKD. Clin J Am Soc Nephrol. 2015; 10(12):2136-2142.
7. Chernin G, Gal-Oz A, Ben-Assa E, et al. Secondary prevention of hyperkalemia with sodium polystyrene sulfonate in cardiac and kidney patients on renin-angiotensin-aldosterone system inhibition therapy. Clin Cardiol. 2012;35(1):32-36.
8. Harel Z, Harel S, Shah PS, et al. Gastrointestinal adverse events with sodium polystyrene sulfonate (Kayexalate) use: a systematic review. Am J Med. 2013;126(3):264.e9-e24.
9. FDA. Safety warning: Kayexalate (sodium polystyrene sulfonate) powder. www.fda.gov/Safety/MedWatch/SafetyInformation/ucm186845.htm. Accessed February 15, 2017.
10. FDA. FDA drug safety communication: FDA required drug interaction studies with potassium-lowering drug Kayexalate (sodium polystyrene sulfonate). www.fda.gov/Drugs/DrugSafety/ucm468035.htm. Accessed March 1, 2017.
11. Veltassa® (patiromer) [package insert]. Redwood City, CA: Relypsa, Inc; 2016. www.veltassa.com/pi.pdf. Accessed March 1, 2017.
12. AstraZeneca. FDA accepts for review New Drug Application for sodium zirconium cyclosilicate (ZS-9) for the treatment of hyperkalaemia. www.astrazeneca.com/investor-relations/Stock-exchange-announcements/fda-accepts-for-review-new-drug-application-for-sodium-zirconium-18102016.html. Accessed March 1, 2017.
1. Gilbert S, Weiner D, Gipson D, eds; National Kidney Foundation. Primer on Kidney Diseases. 6th ed. Philadelphia, PA: Saunders Elsevier; 2014.
2. Einhorn LM, Zhan M, Hsu VD, et al. The frequency of hyperkalemia and its significance in chronic kidney disease. Arch Intern Med. 2009;169(12):1156-1162.
3. Flinn RB, Merrill JP, Welzant WR. Treatment of the oliguric patient with a new sodium-exchange resin and sorbitol: a preliminary report. N Engl J Med. 1961;264:111-115.
4. Dunn JD, Benton WW, Orozco-Torrentera E, Adamson RT. The burden of hyperkalemia in patients with cardiovascular and renal disease. Am J Manag Care. 2015;21(15 suppl): s307-s315.
5. Li L, Harrison SD, Cope MJ, et al. Mechanism of action and pharmacology of patiromer, a nonabsorbed cross-linked polymer that lowers serum potassium concentration in patients with hyperkalemia. J Cardiovasc Pharmacol Ther. 2016;21(5):456-465.
6. Lepage L, Dufour AC, Doiron J, et al. Randomized clinical trial of sodium polystyrene sulfonate for the treatment of mild hyperkalemia in CKD. Clin J Am Soc Nephrol. 2015; 10(12):2136-2142.
7. Chernin G, Gal-Oz A, Ben-Assa E, et al. Secondary prevention of hyperkalemia with sodium polystyrene sulfonate in cardiac and kidney patients on renin-angiotensin-aldosterone system inhibition therapy. Clin Cardiol. 2012;35(1):32-36.
8. Harel Z, Harel S, Shah PS, et al. Gastrointestinal adverse events with sodium polystyrene sulfonate (Kayexalate) use: a systematic review. Am J Med. 2013;126(3):264.e9-e24.
9. FDA. Safety warning: Kayexalate (sodium polystyrene sulfonate) powder. www.fda.gov/Safety/MedWatch/SafetyInformation/ucm186845.htm. Accessed February 15, 2017.
10. FDA. FDA drug safety communication: FDA required drug interaction studies with potassium-lowering drug Kayexalate (sodium polystyrene sulfonate). www.fda.gov/Drugs/DrugSafety/ucm468035.htm. Accessed March 1, 2017.
11. Veltassa® (patiromer) [package insert]. Redwood City, CA: Relypsa, Inc; 2016. www.veltassa.com/pi.pdf. Accessed March 1, 2017.
12. AstraZeneca. FDA accepts for review New Drug Application for sodium zirconium cyclosilicate (ZS-9) for the treatment of hyperkalaemia. www.astrazeneca.com/investor-relations/Stock-exchange-announcements/fda-accepts-for-review-new-drug-application-for-sodium-zirconium-18102016.html. Accessed March 1, 2017.