spironolactone, Aldactone (cont.)

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DOSING: Spironolactone may be taken with or without food. The dosage range is 25-400 mg daily in single or divided doses.

  • The initial dose for treating edema in adults is 100 mg daily as a single dose or divided doses. The dose may be adjusted after 5 days based on response. The recommended dose range is 25 to 200 mg daily.
  • The dose for treating high blood pressure (hypertension) is 50 to 100 mg daily in single or divided doses.
  • The dose for treating hypokalemia is 25 to 100 mg daily.

DRUG INTERACTIONS: Spironolactone can lower blood sodium levels while raising blood potassium levels. Excessively high blood potassium levels can lead to potentially life-threatening abnormalities in the rhythm of the heart. Therefore, spironolactone usually is not administered with other agents that can raise blood potassium levels, such as potassium supplements, angiotensin converting enzyme (ACE) inhibitors [for example, enalapril (Vasotec)], indomethacin (Indocin), or other potassium-sparing diuretics. Spironolactone can cause elevation of blood digoxin (Lanoxin) to toxic levels, requiring adjustment of the digoxin dosage.

PREGNANCY: There are no adequate studies in pregnant women. Spironolactone may be harmful if used for treating gestational hypertension (high blood pressure during pregnancy).

NURSING MOTHERS: An active metabolite of spironolactone is secreted in breast milk. To avoid adverse effects in the newborn, mothers should avoid breastfeeding while taking spironolactone.

SIDE EFFECTS: Side effects of spironolactone include headache, diarrhea, cramps, drowsiness, rash, nausea, vomiting, impotence, irregular menstrual periods, and irregular hair growth. Fluid and electrolytes imbalance (for example, low sodium, low magnesium, and high potassium) may occur, so patients should be monitored carefully. Enlargement of the breasts (gynecomastia) may also occur and is related to dose and duration of therapy. It usually reverses upon discontinuation of spironolactone.

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 8/6/2014


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