Hypoaldosteronism is a condition where your body produces too little aldosterone, a hormone made by the adrenal glands that controls how your kidneys handle sodium, potassium, and water. Without enough aldosterone, potassium builds up in the blood, sodium drops, and the body struggles to maintain normal blood pressure and acid balance. It is most common in people with chronic kidney disease, particularly those with diabetic kidney damage.
What Aldosterone Does in Your Body
Aldosterone acts on cells in the final stretch of the kidney’s filtering tubes, called the distal tubule and collecting ducts. It tells these cells to pull sodium back into the bloodstream while pushing potassium out into the urine. Specifically, aldosterone increases the number of sodium channels on the inner surface of these kidney cells and boosts the activity of pumps on the outer surface that trade sodium for potassium. Every time a sodium ion gets reabsorbed, a potassium ion moves the other direction and is eventually excreted.
This sodium reabsorption also draws water back into the blood, which helps maintain blood volume and blood pressure. When aldosterone levels drop, you lose more sodium and water in urine while retaining too much potassium. The downstream effects touch your blood pressure, your heart rhythm, and even how well your body manages its acid-base balance.
Types and Causes
Hypoaldosteronism is generally grouped into three categories based on where the problem originates.
Defective Synthesis (Hyperreninemic)
In this form, the adrenal glands themselves fail to produce aldosterone even though the signaling system telling them to do so is working fine. Renin, the enzyme the kidneys release to trigger aldosterone production, is elevated because the body senses that aldosterone is missing and keeps calling for more. Causes include genetic enzyme deficiencies that block the hormone’s production pathway, direct damage to adrenal tissue from autoimmune disease or infection, and certain medications that suppress adrenal function.
Defective Release (Hyporeninemic)
This is the most common form in adults. Here, the kidneys themselves stop producing enough renin, so the signal to make aldosterone never arrives at the adrenal glands. Diabetic kidney disease is the leading cause: chronic high blood sugar damages the specialized kidney cells (the juxtaglomerular apparatus) that produce renin. Other conditions linked to this form include chronic kidney disease from other causes, autonomic neuropathy, sickle cell disease, and HIV infection.
Aldosterone Resistance (Pseudohypoaldosteronism)
Sometimes aldosterone levels are actually normal or even high, but the kidneys don’t respond to it. This is called pseudohypoaldosteronism. The autosomal recessive form results from mutations in the epithelial sodium channel, the actual gateway that lets sodium back into kidney cells. The autosomal dominant form involves mutations in the receptor that aldosterone binds to. A separate variant, Type II pseudohypoaldosteronism, stems from mutations in kinase enzymes that regulate sodium and potassium transporters in the kidney. Potassium-sparing diuretics can also block aldosterone’s effects and mimic this condition.
How Common It Is
Hypoaldosteronism is particularly prevalent among people with chronic kidney disease who develop high potassium. A study in Kidney International measured aldosterone levels in 31 patients with chronic kidney impairment and elevated potassium. Of those 31 patients, 23 (roughly 74%) had aldosterone levels that were inappropriately low relative to their potassium levels. In healthy people, high potassium naturally stimulates more aldosterone production, but in these patients that feedback loop was broken. The researchers confirmed that the aldosterone deficiency directly contributed to the dangerous potassium elevation.
Symptoms and What They Feel Like
The symptoms of hypoaldosteronism are driven primarily by high potassium and low sodium. High potassium (hyperkalemia) affects nerve and muscle signaling, particularly in the heart. You might notice muscle weakness, fatigue, tingling or numbness, and in severe cases, dangerous heart rhythm disturbances. Mild hyperkalemia often produces no obvious symptoms at all, which is one reason the condition frequently goes undetected until blood work reveals it.
Low sodium and reduced blood volume can cause lightheadedness when you stand up (orthostatic hypotension), general fatigue, and in more pronounced cases, dehydration. Some people notice salt cravings as the body tries to compensate for what it’s losing in urine.
The Link to Type 4 Renal Tubular Acidosis
One of the most clinically significant consequences of hypoaldosteronism is a condition called type 4 renal tubular acidosis (RTA), which is the most common form of RTA in the United States and worldwide. When aldosterone is low, potassium accumulates. That excess potassium impairs the kidney’s ability to produce ammonia, a molecule the kidneys normally use to neutralize acid and flush it out in urine. With less ammonia available, acid builds up in the blood, creating a mild but persistent metabolic acidosis.
An important detail: unlike other forms of RTA, people with type 4 RTA can still acidify their urine to a pH below 5.5. The problem isn’t a total inability to excrete acid, it’s that there simply isn’t enough ammonia to buffer a sufficient amount of it. The kidneys also lose excess sodium in the urine even when dietary sodium is restricted, a hallmark sign of aldosterone deficiency. Diabetic nephropathy is by far the most common driver, with vascular damage to renin-producing kidney cells creating a chain reaction of low renin, low aldosterone, high potassium, and acidosis.
How It’s Diagnosed
Diagnosis starts with routine blood work showing persistently elevated potassium and sometimes low sodium or mild acidosis in someone without an obvious dietary or medication explanation. From there, measuring both aldosterone levels and renin activity helps pinpoint the type. If renin is high but aldosterone is low, the problem is in the adrenal glands (hyperreninemic hypoaldosteronism). If both renin and aldosterone are low, the problem originates in the kidneys (hyporeninemic). If aldosterone is normal or high but potassium is still elevated, pseudohypoaldosteronism is suspected.
Urine sodium levels provide another clue. In hypoaldosteronism, urine sodium stays persistently high even when salt intake is restricted, reflecting the kidney’s inability to hold onto sodium without aldosterone’s signal.
Treatment Options
Treatment depends on the underlying cause and severity but generally focuses on replacing what’s missing and managing potassium levels.
- Fludrocortisone: This is a synthetic version of the hormones aldosterone mimics. The typical starting dose is 0.1 mg daily, which can be adjusted up to 0.2 mg. If blood pressure rises too much, the dose is reduced. It works by doing what aldosterone normally does: telling the kidneys to retain sodium and excrete potassium.
- Dietary potassium restriction: Reducing high-potassium foods (bananas, potatoes, tomatoes, orange juice, beans) helps keep blood levels in a safer range while other treatments take effect.
- Treating the underlying condition: In hyporeninemic forms, better blood sugar control in diabetes can slow further kidney damage. Stopping medications that suppress renin or aldosterone (certain blood pressure drugs, potassium-sparing diuretics, anti-inflammatory drugs) may resolve the problem entirely.
- Loop diuretics: These increase potassium excretion through the kidneys and are sometimes used alongside fludrocortisone, particularly in patients with kidney disease where fludrocortisone alone might cause fluid retention.
Blood pressure, potassium, and sodium levels need regular monitoring during treatment. Fludrocortisone can cause fluid retention, swelling in the feet, and elevated blood pressure if the dose is too high. Finding the right balance often requires a few weeks of adjustment.