Aldosterone is a steroid hormone produced by the adrenal glands that maintains fluid and electrolyte balance. It acts on the kidneys to increase the reabsorption of sodium and water into the bloodstream while promoting potassium excretion. This action directly influences blood volume and blood pressure. When aldosterone levels are too low (hypoaldosteronism), the body loses excessive sodium and water, causing dehydration and dangerously low blood pressure. Managing this condition prevents serious health complications related to volume depletion and electrolyte imbalance.
Understanding Low Aldosterone
Hypoaldosteronism occurs when the hormone is produced inadequately or when the kidneys cannot respond effectively. Common causes include primary adrenal insufficiency, where damaged adrenal glands cannot produce sufficient aldosterone, or specific enzyme deficiencies. Certain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs) or Angiotensin-Converting Enzyme (ACE) inhibitors, can also contribute.
A distinct form, hyporeninemic hypoaldosteronism, often affects older adults with diabetes or chronic kidney disease. In this case, the body fails to produce the necessary stimulus (renin) to trigger aldosterone release. Symptoms are related to electrolyte imbalance and low blood volume, including persistent fatigue, muscle weakness, and a strong craving for salt.
The most serious clinical signs are chronic low blood pressure, often causing dizziness upon standing (orthostatic hypotension), and electrolyte changes. Low aldosterone leads to low serum sodium (hyponatremia) and elevated serum potassium (hyperkalemia). High potassium levels can disrupt normal heart rhythm, requiring diagnosis before treatment begins.
Medical Approaches to Raising Aldosterone
For confirmed hypoaldosteronism, standard medical treatment involves replacement therapy using a synthetic mineralocorticoid. The most common medication is fludrocortisone, which mimics natural aldosterone. It acts on mineralocorticoid receptors in the renal tubules, promoting sodium and water retention to restore blood volume and blood pressure.
The therapy’s goal is to normalize electrolyte levels, particularly correcting volume depletion and bringing serum potassium into a safe range. Dosage must be carefully titrated by a prescribing physician, usually an endocrinologist, based on the patient’s needs. A typical adult starting dose ranges from 0.05 to 0.2 milligrams daily, taken orally.
Effectiveness is monitored via clinical and laboratory markers, not by measuring aldosterone itself. Strict medical oversight is required because the drug is potent and needs ongoing adjustments, especially during physical stress or illness. Patients undergo regular blood work to maintain electrolyte balance and prevent over-correction. Fludrocortisone therapy is often a lifelong strategy for severe deficiency.
Dietary and Lifestyle Methods
While medical replacement is essential for severe deficiency, dietary and lifestyle adjustments can support management or address milder cases. The most direct non-pharmaceutical method to counteract low aldosterone is increasing dietary sodium intake. Since the kidneys lose salt due to the deficiency, a high-sodium diet helps maintain adequate blood volume and prevents hyponatremia.
Patients, in consultation with a physician, may be advised to consume a high-sodium diet, salt tablets, or electrolyte solutions. While insufficient as a standalone treatment for true hypoaldosteronism, this serves as an important addition to medication. Adequate fluid intake is also necessary to support the blood volume expansion facilitated by the extra sodium.
Another focus involves managing potassium intake, as low aldosterone impairs the body’s ability to excrete this electrolyte, leading to hyperkalemia. Patients should limit high-potassium foods and avoid potassium-containing salt substitutes. To manage low blood pressure upon standing, positional maneuvers are beneficial, such as crossing the legs or tightening abdominal muscles before standing up. This increases venous return and helps reduce orthostatic hypotension symptoms.
Monitoring Treatment and Recognizing Over-Correction
Successful treatment requires continuous monitoring to ensure effective management without adverse effects. Physicians rely on clinical assessments and laboratory tests. Clinical parameters include regular monitoring of blood pressure (comparing sitting and standing measurements) and checking for signs of fluid retention, such as weight gain or edema.
Laboratory monitoring focuses primarily on serum electrolytes (sodium and potassium) to restore them to normal levels. Plasma renin activity (PRA) is also a marker; since low aldosterone causes high renin levels, successful replacement therapy should bring the PRA back down. These measurements help fine-tune the fludrocortisone dosage.
A danger of treatment is over-correction, resulting in iatrogenic hyperaldosteronism. Signs of over-correction include hypertension, excessive fluid retention (edema), and dangerously low potassium (hypokalemia). Hypokalemia can cause muscle weakness and potentially life-threatening cardiac arrhythmias, requiring immediate medical attention and medication adjustment.