Spironolactone
Administration
- Type: Antihypertensive; potassium sparing diuretic; aldosterone receptor antagonist
- Dosage Forms: 25,50,100
- Routes of Administration: Oral
- Common Trade Names: Aldactone
Adult Dosing
Edema
- 25-200mg/day PO divided QD-bid
- For edema associated with CHF, cirrhosis, or nephrotic syndrome
Hypertension
- 25-50mg/day PO divided QD-bid
- Start: 12.5mg PO QD
Hyperaldosteronism, primary
- 100-400mg PO QD
Hypokalemia, diuretic-induced
- 25-100mg/day PO divided QD-QID
CHF, NYHA Class III/IV
- 25mg PO QD
- Use with standard treatment; may increase to 50mg/day after 8wk for worsening CHF if K stable
- May decrease to 25mg qod if hyperkalemia; hold if K >5 mEq/L or creatinine >4mg/dL
Hirsutism, idiopathic
- 50-200mg PO QD
- Off label use
Acne vulgaris
- 50-200mg PO QD
- Start: 25mg PO QD
- Off label use
Pediatric Dosing
Edema
- 1-3.3mg/kg/day PO divided QD-QID
- Max: 3.3mg/kg/day up to 200mg/day
- Off label use
Hyperaldosteronism test
- 125-375mg/m^2/day PO divided bid-QID
- Max: 375mg/m^2/day
- Off label use
Special Populations
Renal Dosing
- CrCl <10, anuria, or acute renal impairment: contraindicated
Hepatic Dosing
- Caution advised with hepatic impairment
Contraindications
- Allergy to class/drug
- CrCl <10
- anuria
- renal impairment, acute
- hyperkalemia
- Addison disease
Adverse Reactions
Serious
- anaphylaxis
- Stevens-Johnson syndrome
- toxic epidermal necrolysis
- drug reaction with eosinophilia and systemic sx
- vasculitis
- hepatotoxicity
- renal failure
- electrolyte imbalance
- hyperkalemia, severe
- arrhythmias
- leukopenia
- agranulocytosis
- thrombocytopenia
Common
- nausea/vomiting
- abdominal cramps/pain
- muscle cramps
- diarrhea
- headache
- confusion
- dizziness
- somnolence
Pharmacology
- Half-life: 1.3-2h (parent drug), 13.8-16.5h (active metabolites)
- Metabolism: Liver
- Excretion: Urine
Mechanism of Action
Antagonizes aldosterone receptors in the distal convoluted tubule, decreasing Na and water reabsorption and increasing K retention
Comments
See Also
References
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