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Medical and Pharmacy Editor:

Brand Name: Aldactone

Generic Name: Spironolactone

Drug Class: Aldosterone Antagonists, Selective; Diuretics, Potassium-Sparing

What Is Spironolactone and How Does It Work?

Spironolactone is used to treat high blood pressure and heart failure. Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems. It is also used to treat swelling (edema) caused by certain conditions (such as heart failure, liver disease) by removing excess fluid and improving symptoms such as breathing problems.

Spironolactone is also used to treat low potassium levels and conditions in which the body is making too much of a natural chemical (aldosterone).

Spironolactone is known as a "water pill" (potassium-sparing diuretic).

Spironolactone has also been used to treat excessive hair growth (hirsutism) in women with polycystic ovary disease.

Spironolactone is available under the following different brand names: Aldactone.

Dosages of Spironolactone

Adult and Pediatric Dosage Forms and Strengths


  • 25 mg
  • 50 mg
  • 100 mg

Dosage Considerations – Should be Given as Follows:

Primary Hyperaldosteronism

As a diagnostic agent

  • Long test: 400 mg orally once/day for 3-4 weeks
  • Short test: 400 mg orally once/day for 4 days

Short-term perioperative treatment for adrenalectomy

  • Initial: 100-400 mg orally once/day in preparation for surgery
  • Maintenance: Lowest effective dose individualized for patient

Geriatric, Initial: 400 mg/day orally, THEN 100-300 mg/day

Edematous Conditions

  • Cirrhosis of the liver with edema and/or ascites; nephrotic syndrome
  • Initial: 100 mg once/day or divided every 12 hours for 5 days; if no clinical response, add second diuretic with more specific mechanism of action
  • Range: 25-200 mg orally once/day or divided every 12 hours

Edema, Pediatric (Off-label)

  • CHF, cirrhosis, ascites, and nephrotic syndrome
  • 1-3.3 mg/kg/day orally or divided every 12 hours; not to exceed 3.3 mg/kg/day or up to 100 mg/day

Essential Hypertension

  • Adult, Initial: 25-100 mg orally once/day or divided every 12 hours for more than 2 weeks; adjust to patient response
  • Pediatric: Among therapeutic options recommended by the National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents
  • 1-3.3 mg/kg/day orally or divided every 12 hours; not to exceed 3.3 mg/kg/day or up to 100 mg/day

Congestive Heart Failure

Adult and Geriatric

  • Indicated for NYHA class II/IV heart failure (provided CrCl greater than 30 mL/min and serum K less than 5 mEq/dL)
  • Initial: 25 mg orally once/day
  • Range: 12.5-25 mg/day orally; may increase to 50 mg/day if needed; if 25 mg/day not tolerated, reduce to 25 mg every other day
  • ACC/AHA guidelines recommend aldosterone antagonist to be added to an ACEI or ARB, plus a beta-blocker; patient conditions may also require additional medications (e.g., loop diuretics, hydralazine, nitrates, digoxin)


  • Range: 25-100 mg orally once/day

Diuresis, Geriatric

    12.5 mg orally once/day in 1-2 divided doses; increase by 25-50 mg every 5 days as needed; adjust for renal impairment

Hirsutism (Off-label)

Women with hirsutism

    50-200 mg orally once/day or divided every 12 hours

Acne (Off-label)

Females with hormonal acne

    50-200 mg orally once/day or divided every 12 hours

Hyperaldosteronism (Orphan), Pediatric

Orphan designation for primary hyperaldosteronism


  • CMP Pharma, Inc; orally Box 147, 8026 US Highway 264A; Farmville, NC 27828

Dosing Modifications

Renal impairment

  • CrCl greater than or equal to 50 mL/min/1.73 m: 12.5-25 mg once/day; use maintenance dose of 25 mg once/day or every 12 hours after 4 weeks of treatment with potassium less than or equal to 5 mEq/L
  • CrCl 30-49 mL/min/1.73 m: 12.5 mg once/day or every other day; use maintenance dose of 12.5-25 mg once/day after 4 weeks of treatment with potassium less than or equal to 5 mEq/L
  • CrCl less than 30 mL/min/1.73 m: Avoid use

Dosing considerations


  • Caution with heart failure and avoid with CrCl less than 30 mL/min (Beers criteria)
  • In heart failure, the risk of hyperkalemia is higher in older adults, especially if taking greater than 25 mg/day or with concomitant NSAID, ACE inhibitor, ARB, or potassium supplement

Overdose Management

  • May use normal saline for volume replacement
  • May use dopamine or norepinephrine to treat hypotension
  • Treat hyperkalemia with IV glucose (dextrose 25% in water), concurrently with rapid-acting insulin and IV sodium bicarbonate; oral/rectal solutions of Kayexalate in sorbitol can be used if needed
  • If dysrhythmia due to decreased K+ or Mg+ suspected, replace aggressively
  • Discontinue treatment if no symptoms after 6 hours
Medically Reviewed by a Doctor on 1/11/2018

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