Pregnancy Risk Category D
How supplied
Tablets: 25 mg, 50 mg, 100 mg
Action
A potassium-sparing diuretic that antagonizes aldosterone in the distal tubules, increasing sodium and water excretion.
Indications & dosage
Edema--
Adults: 25 to 200 mg P.O. daily or in two to four divided doses.
Children: 3.3 mg/kg P.O. daily or in divided doses.
Hypertension--
Adults: 50 to 100 mg P.O. daily or in divided doses.
Diuretic-induced hypokalemia--
Adults: 25 to 100 mg P.O. daily.
Detection of primary hyperaldosteronism--
Adults: 400 mg P.O. daily for 4 days (short test) or 3 to 4 weeks (long test). If hypokalemia and hypertension are corrected, a presumptive diagnosis of primary hyperaldosteronism is made.
Management of primary hyperaldosteronism--
Adults: 100 to 400 mg P.O. daily. Use lowest effective dose.
Adverse reactions
CNS: headache, drowsiness, lethargy, confusion, ataxia.
GI: diarrhea, gastric bleeding, ulceration, cramping, gastritis, vomiting.
GU: transient elevation in BUN levels; inability to maintain erection; gynecomastia, breast soreness, and menstrual disturbances.
Hematologic: agranulocytosis.
Metabolic: hyponatremia, hyperkalemia, dehydration, mild acidosis.
Skin: urticaria, hirsutism, maculopapular eruptions.
Other: drug fever, anaphylaxis.
Interactions
Drug-drug. ACE inhibitors, indomethacin, other potassium-sparing diuretics, potassium supplements: increased risk of hyperkalemia. Use together cautiously, especially in patients with renal impairment.
Aspirin: possible blocked diuretic effect of spironolactone. Watch for diminished spironolactone response.
Digoxin: may alter digoxin clearance, increasing risk of digoxin toxicity. Monitor digoxin levels.
Drug-food. Potassium-containing salt substitutes, potassium-rich foods (such as citrus fruits, tomatoes): increased risk of hyperkalemia. Use low-potassium salt substitutes. Ingest high-potassium foods cautiously.
Drug-herb. Licorice: may block ulcer healing and aldosterone-like effects of licorice. Avoid concomitant use.
Effects on diagnostic tests
Drug therapy alters fluorometric determinations of plasma and urinary
17-hydroxycorticosteroid levels and may cause false elevations on radioimmunoassay of serum digoxin.
Contraindications
Contraindicated in patients with known hypersensitivity to drug and in those with anuria, acute or progressive renal insufficiency, or hyperkalemia.
Nursing considerations
Patient teaching
*Liquid contains alcohol. **May contain tartrazine. †Canada ‡Australia §U.K. OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING