What is the primary treatment for hypoaldosteronism?

Treatment of Hypoaldosteronism

The primary treatment for hypoaldosteronism is fludrocortisone (Florinef) at a dose of 50-200 μg once daily, taken in the morning, along with liberal salt intake. 1, 2

Types of Hypoaldosteronism

• Primary adrenal insufficiency (Addison's disease) involves deficiency of both cortisol and aldosterone, requiring both glucocorticoid and mineralocorticoid replacement 1
• Isolated hypoaldosteronism (hyporeninemic hypoaldosteronism) is more common in older adults with diabetes and/or kidney disease, requiring only mineralocorticoid replacement 3, 4

Treatment Algorithm

For Primary Adrenal Insufficiency:

1. Glucocorticoid replacement:

   • Hydrocortisone 15-25 mg daily in divided doses (first dose upon waking, last dose at least 6 hours before bedtime) 1
   • Alternative: cortisone acetate 18.75-31.25 mg daily in divided doses 1

2. Mineralocorticoid replacement:

   • Fludrocortisone 50-200 μg once daily in the morning 1
   • Higher doses may be needed in children and younger adults 1

3. Salt intake:

   • Encourage unrestricted salt and salty food consumption 1
   • Avoid potassium-containing salt substitutes 1

For Isolated Hypoaldosteronism:

1. Fludrocortisone 50-200 μg once daily 3, 5
2. Dietary potassium restriction as a general measure 3
3. Additional options if hyperkalemia persists:
   • Loop diuretics 3, 5
   • Sodium bicarbonate for metabolic acidosis 3, 5
   • Potassium-binding resins in severe cases 5

Monitoring Treatment

• Clinical parameters:

  • Blood pressure (sitting and standing) to assess for postural hypotension 1
  • Weight to detect fluid retention 1
  • Presence of peripheral edema 1
  • Salt cravings or lightheadedness 1

• Laboratory monitoring:

  • Serum electrolytes (sodium and potassium) 1, 6
  • Plasma renin activity (PRA) - aim for upper normal range 6
  • Acid-base status if indicated 5

Special Situations

Pregnancy

• Fludrocortisone dose may need to be increased during late pregnancy due to anti-mineralocorticoid effects of progesterone 1, 6
• Monitor salt cravings, blood pressure, and serum electrolytes rather than PRA during pregnancy 1

Hypertension

• If essential hypertension develops, reduce fludrocortisone dose but do not discontinue 1
• Consider adding a vasodilator rather than stopping mineralocorticoid replacement 1

Medication Interactions

• Avoid:

  • Diuretics 1
  • Acetazolamide 1
  • NSAIDs 1
  • Licorice and grapefruit juice (potentiate mineralocorticoid effect) 1

• May need dose adjustment:

  • Drospirenone-containing contraceptives (may need more fludrocortisone) 1

Common Pitfalls

• Under-replacement with mineralocorticoids is common and may be compensated by over-replacement with glucocorticoids 1
• Failure to recognize hypoaldosteronism in patients with hyperkalemia, hyponatremia, and metabolic acidosis, particularly in older adults with diabetes or kidney disease 4
• Inadequate salt intake can compromise the effectiveness of mineralocorticoid replacement 1
• Not adjusting fludrocortisone dose during pregnancy or in hot weather 6