👤 By the CinnaRN Clinical Content Team🕐 Updated 2026-08-23🏷️ Pharmacological Therapies🔖 Free to read, print, and share
Also known as: Aldactone · potassium-sparing diuretic · aldosterone antagonist · water pill
💡
Use this quick-reference guide to spot, treat, and prevent Spironolactone on the NCLEX. Keep it handy during review and on exam day!
🩺
📒 The 1-minute cheat sheet
📌 Uses
HF, HTN, ascites, hyperaldosterone
Aldosterone antagonist → keeps K+
🧪 Labs
K+ > 5.0 mEq/L → HOLD
Monitor K+, renal function
🚩 Report
Muscle weakness, peaked T waves
Irregular pulse → arrhythmia
📌 Avoid
NO K+ supplements / salt substitutes
Avoid high-K+ foods (banana, orange)
🎓 Teach
Gynecomastia possible (males)
Take in AM, report ED/menstrual change
📚 Spironolactone — full study notes
The cheat sheet above is your quick recall card. These notes go deeper — what it is, what to do first, what must be reported, and what to teach.
Spironolactone is a potassium-sparing diuretic and aldosterone antagonist used for heart failure, hypertension, edema, hyperaldosteronism, and ascites. It promotes sodium and water excretion while retaining potassium. The dominant safety concern is hyperkalemia.
🔑
Key points
Understand these first
Blocks aldosterone, causing loss of sodium and water but retention of potassium (potassium-sparing).
Hyperkalemia is the major risk, increased by potassium supplements, salt substitutes, ACE inhibitors, and ARBs.
Improves survival in chronic heart failure with reduced ejection fraction.
Endocrine effects include gynecomastia, breast tenderness, and menstrual irregularities.
Onset of diuretic effect is gradual (days) compared with loop diuretics.
Best taken in the morning to avoid nighttime urination.
✅
Nursing priorities
What to do, in order
Monitor serum potassium and renal function regularly and report hyperkalemia.
Teach the patient to avoid potassium supplements and potassium-based salt substitutes.
Assess fluid status: daily weights, intake and output, edema, and blood pressure.
Administer in the morning and assess for endocrine side effects.
🚩
Red flags — report now
Escalate immediately
Report serum potassium above 5.0 mEq/L and signs of hyperkalemia: muscle weakness, paresthesias, or irregular pulse.
Report peaked T waves or other ECG changes consistent with hyperkalemia.
Combining with ACE inhibitors or ARBs without monitoring can cause dangerous hyperkalemia.
🧪
Labs & values
Numbers to know
Serum potassium (normal 3.5-5.0 mEq/L; hold and report if above 5.0)
BUN (normal 10-20 mg/dL)
Serum creatinine (normal about 0.6-1.2 mg/dL)
Serum sodium (normal 135-145 mEq/L)
🗣️
Patient teaching
What patients must know
Avoid salt substitutes and potassium supplements unless your provider approves them.
Report muscle weakness, numbness, tingling, or an irregular heartbeat.
Take the medication in the morning to limit nighttime urination.
Weigh yourself daily and report a gain of 2-3 pounds in a day or 5 pounds in a week.
Report breast tenderness or enlargement, which can occur and may be reversible.
❓ Spironolactone: NCLEX FAQs
What are the priority nursing interventions for Spironolactone?
Monitor serum potassium and renal function regularly and report hyperkalemia. Teach the patient to avoid potassium supplements and potassium-based salt substitutes. Assess fluid status: daily weights, intake and output, edema, and blood pressure. Administer in the morning and assess for endocrine side effects.
What are the warning signs of Spironolactone a nurse must report?
Report serum potassium above 5.0 mEq/L and signs of hyperkalemia: muscle weakness, paresthesias, or irregular pulse. Report peaked T waves or other ECG changes consistent with hyperkalemia. Combining with ACE inhibitors or ARBs without monitoring can cause dangerous hyperkalemia.
What do I need to know about Spironolactone for the NCLEX?
Blocks aldosterone, causing loss of sodium and water but retention of potassium (potassium-sparing). Hyperkalemia is the major risk, increased by potassium supplements, salt substitutes, ACE inhibitors, and ARBs. Improves survival in chronic heart failure with reduced ejection fraction. Endocrine effects include gynecomastia, breast tenderness, and menstrual irregularities.
What patient teaching is important for Spironolactone?
Avoid salt substitutes and potassium supplements unless your provider approves them. Report muscle weakness, numbness, tingling, or an irregular heartbeat. Take the medication in the morning to limit nighttime urination. Weigh yourself daily and report a gain of 2-3 pounds in a day or 5 pounds in a week.
✨
Quick Tip
Blocks aldosterone, causing loss of sodium and water but retention of potassium (potassium-sparing).