Classifications: electrolye & water balance agent; selective aldosterone receptor antagonist (sara); antihypertensive; Therapeutic: antihypertensive; diuretic; sara
Pregnancy Category: Spironolactone B
25 mg, 50 mg, 100 mg tablets
Binds to mineralocorticoid receptors and blocks the binding of aldosterone, a component of the renin-angiotensin-aldosterone
system (RAAS). Thus eplerenone blocks the primary effect of aldosterone which is sodium reabsorption.
Lowers blood pressure by inhibiting sodium and water retention, thus reducing total plasma volume.
Treatment of hypertension, alone or with other antihypertensive agents. Adjunctive therapy for post MI heart failure.
Serum potassium >5.5 mEq/L; type 2 diabetes with microalbuminuria; serum creatinine >2.0 mg/dL in males or >1.8 mg/dL in females;
creatinine clearance <50 mL/min; concomitant treatment with potassium supplements or potassium-sparing diuretics (amiloride,
spironolactone, or triamterene), or strong inhibitors of CYP450 3A4 (e.g., ketoconazole, itraconazole); lactation.
Hepatic impairment; concomitant use of another mineralocorticoid receptor blocker and ACE inhibitors or angiotensin II antagonists;
severe hepatic disease; concomitant treatment with moderate inhibitors of CYP450 3A4 (e.g., fluconazole, erythromycin, verapamil,
saquinavir); pregnancy (category B); safety and efficacy in children, infants, or neonates are not established.
Route & Dosage
Adult: PO 50 mg once daily, may be increased to 50 mg b.i.d. or 100 mg q.d., if inadequate response after 4 wk
Do not administer if Clcr <50 mL/min due to risk of hyperkalemia.
Adverse Effects (≥1%)Body as a Whole: Fatigue
, flu-like syndrome. CNS:
Headache, dizziness. CV:
Diarrhea, abdominal pain. Endocrine:
Gynecomastia. Metabolic: Hyperkalemia
, increased GGT, hypercholesterolemia, hypertriglyceridemia, decreased sodium levels. Respiratory:
Albuminuria, abnormal vaginal bleeding.
InteractionsDrug: ace inhibitors
, angiotensin ii receptor blockers
, azole antifungals
(e.g., fluconazole, itraconazole, ketoconazole
), erythromycin, saquinavir, verapamil
may increase risk of hyperkalemia. Food: Potassium
-containing salt substitutes
may increase risk of hyperkalemia.
Rapidly absorbed. Peak:
1.5 h. Distribution:
50% protein bound, primarily to alpha1
-acid glycoproteins. Metabolism:
In liver by CYP3A4. Elimination:
32% in feces, 67% in urine. Half-Life:
Assessment & Drug Effects
- Monitor cardiovascular status with frequent BP determinations. Note that BP lowering usually occurs within 2 wk with maximal
antihypertensive effects achieved within 4 wk.
- Lab tests: Monitor baseline and periodic serum potassium, serum sodium, renal function tests, lipid profile, and LFTs. Monitor
type 2 diabetics for microalbuminuria.
- Concurrent drugs: Monitor serum potassium levels more frequently when patient also receiving an ACE inhibitor or an angiontensin
II receptor antagonist. Monitor frequently for lithium toxicity with concurrent use.
- Withhold drug and notify physician for any of the following: serum potassium >5.5 mEq/L, serum creatinine >2.0 mg/dL in males
or >1.8 mg/dL in females, creatinine clearance <50 mL/min, microalbuminuria in type 2 diabetics.
Patient & Family Education
- Do not use potassium supplements, salt substitutes containing potassium, or contraindicated drugs (e.g., ketoconazole, itraconazole)
without consulting physician.
- Do not use OTC nonsteroidal anti-inflammatory drugs without consulting physician.
- Do not drive or operate machinery until reaction to drug is known. It may cause dizziness.