From the Guidelines
To manage renal potassium wasting in patients on ACEi or ARBs, first identify and address any underlying causes such as diuretic use, magnesium deficiency, or other medications, and consider reducing the dose or discontinuing ACEi or ARB in the setting of uncontrolled hyperkalemia despite medical treatment, as recommended by the KDIGO 2024 clinical practice guideline 1.
Key Considerations
- Potassium supplementation is the primary intervention, typically starting with oral potassium chloride 20-40 mEq daily, divided into 2-3 doses to minimize gastrointestinal side effects.
- Potassium-sparing diuretics can be added if supplementation alone is insufficient - options include spironolactone (25-100 mg daily), eplerenone (25-50 mg daily), or amiloride (5-10 mg daily).
- Dietary modifications are also important, encouraging consumption of potassium-rich foods like bananas, oranges, potatoes, and leafy greens.
- Regular monitoring of serum potassium, typically every 1-2 weeks initially then every 3-6 months once stable, is essential, with target potassium levels maintained within the normal range (3.5-5.0 mEq/L) as suggested by the KDIGO 2022 clinical practice guideline 1.
Underlying Causes
- Diuretic use
- Magnesium deficiency
- Other medications
Treatment Approach
- Identify and address underlying causes
- Potassium supplementation
- Potassium-sparing diuretics
- Dietary modifications
- Regular monitoring of serum potassium
Important Considerations
- Addressing magnesium deficiency is particularly important as it can perpetuate potassium wasting through effects on renal potassium channels.
- The KDIGO 2021 clinical practice guideline for the management of blood pressure in chronic kidney disease also recommends considering reducing the dose or discontinuing ACEi or ARB in the setting of uncontrolled hyperkalemia despite medical treatment 1.
- The European Society of Cardiology expert consensus document on the management of hyperkalaemia in patients with cardiovascular disease treated with renin angiotensin aldosterone system inhibitors provides guidance on the management of hyperkalaemia, including the use of loop diuretics and potassium binders 1.
From the FDA Drug Label
DRUG INTERACTIONS 7. 1 Diuretics ... Lisinopril attenuates potassium loss caused by thiazide-type diuretics.
CLINICAL PHARMACOLOGY 12. 1 Mechanism of Action ... The latter decrease may result in a small increase of serum potassium
Managing Renal Potassium Wasting in Patients on ACEi/ARB:
- Monitor serum potassium frequently when using potassium-sparing diuretics with ACEi/ARB.
- Lisinopril attenuates potassium loss caused by thiazide-type diuretics.
- Small increase in serum potassium may occur due to decreased aldosterone secretion.
- In patients with normal renal function, the mean increase in serum potassium was approximately 0.1 mEq/L when treated with lisinopril alone.
- Approximately 15% of patients had increases greater than 0.5 mEq/L and approximately 6% had a decrease greater than 0.5 mEq/L when treated with lisinopril alone 2.
- When treated with lisinopril and hydrochlorothiazide, patients had a mean decrease in serum potassium of 0.1 mEq/L; approximately 4% of patients had increases greater than 0.5 mEq/L and approximately 12% had a decrease greater than 0.5 mEq/L 2.
From the Research
Management of Renal Potassium Wasting in Patients on ACEi/ARB
- The use of Angiotensin-Converting Enzyme inhibitors (ACEi) and Angiotensin Receptor Blockers (ARB) can lead to hyperkalemia, particularly in patients with chronic renal insufficiency 3.
- To manage renal potassium wasting, it is essential to monitor serum potassium levels closely, especially after initiating ACEi/ARB therapy 3.
- Assessing the patient's glomerular filtration rate and baseline serum potassium concentration can help identify those at risk of hyperkalemia 3.
- Patients with excessive potassium intake from diet, supplements, or other medications should be closely monitored, as this can increase the risk of hyperkalemia 3.
Risk Factors for Hyperkalemia
- Chronic renal insufficiency is a significant risk factor for hyperkalemia in patients taking ACEi/ARB 3, 4.
- Anuric hemodialysis patients are also at increased risk of hyperkalemia when taking ACEi/ARB, with a significant increase in serum potassium levels observed in one study 4.
- Hypertensive patients with type II diabetes mellitus may also be at risk of hyperkalemia when taking ACEi/ARB, although one study found no significant difference in renal potassium handling between ACEi and ARB in this population 5.
Treatment and Prevention
- Prompt recognition and treatment of hyperkalemia are crucial to prevent cardiac dysrhythmias and other complications 3.
- Treatment may involve antagonizing the cardiac effects of potassium, redistributing potassium into cells, and removing excess potassium from the body 3.
- In some cases, withdrawal of ACEi/ARB therapy may be necessary to manage hyperkalemia, as seen in a study of anuric hemodialysis patients 4.
- However, another study suggested that acute exposure to ACEi/ARB during an episode of acute kidney injury was not associated with persistent acute kidney disease, and that continued administration of these agents during an episode of AKI or initiation prior to discharge may be safe 6.