Spironolactone

FDA Drug Information • Also known as: Aldactone, Spironolactone

Brand Names: Aldactone, Spironolactone
Drug Class: Aldosterone Antagonist [EPC]
Route: ORAL
Dosage Form: TABLET, COATED
Product Type: HUMAN PRESCRIPTION DRUG

Description

11 DESCRIPTION Spironolactone oral tablets contain 25 mg, 50 mg, or 100 mg of the aldosterone antagonist spironolactone, 17 hydroxy-7α-mercapto-3-oxo-17α-pregn-4-ene-21-carboxylic acid γ-lactone acetate, which has the following structural formula: Spironolactone is practically insoluble in water, soluble in alcohol, and freely soluble in benzene and in chloroform. Inactive ingredients include calcium sulfate, hypromellose, magnesium stearate, microcrystalline cellulose, N & A mint flavor, polyethylene glycol, povidone, pregelatinized corn starch, sodium starch glycolate, talc, and titanium dioxide 20

What Is Spironolactone Used For?

1 INDICATIONS AND USAGE Spironolactone is an aldosterone antagonist indicated for: The treatment of NYHA Class III-IV heart failure and reduced ejection fraction to increase survival, manage edema, and to reduce the need for hospitalization for heart failure ( 1.1 ). Use as an add-on therapy for the treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions ( 1.2 ). The management of edema in adult patients who are cirrhotic when edema is not responsive to fluid and sodium restrictions and in the setting of nephrotic syndrome when treatment of the underlying disease, restriction of fluid and sodium intake, and the use of other diuretics produce an inadequate response ( 1.3 ). Treatment of primary hyperaldosteronism for: ( 1.4 ) Short-term preoperative treatment Long-term maintenance for patients with discrete aldosterone-producing adrenal adenomas who are not candidates for surgery and patients with bilateral micro or macronodular adrenal hyperplasia 1.1 Heart Failure Spironolactone is indicated for treatment of NYHA Class III-IV heart failure and reduced ejection fraction to increase survival, manage edema, and reduce the need for hospitalization for heart failure. Spironolactone is usually administered in conjunction with other heart failure therapies. 1.2 Hypertension Spironolactone is indicated as add-on therapy for the treatment of hypertension, to lower blood pressure in patients who are not adequately controlled on other agents. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes. Control of high blood pressure should be part of comprehensive cardiovascular risk management, including, as appropriate, lipid control, diabetes management, antithrombotic therapy, smoking cessation, exercise, and limited sodium intake. Many patients will require more than one drug to achieve blood pressure goals. For specific advice on goals and management, see published guidelines, such as those of the National High Blood Pressure Education Program’s Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC). Numerous antihypertensive drugs, from a variety of pharmacologic classes and with different mechanisms of action, have been shown in randomized controlled trials to reduce cardiovascular morbidity and mortality, and it can be concluded that it is blood pressure reduction, and not some other pharmacologic property of the drugs, that is largely responsible for those benefits. The largest and most consistent cardiovascular outcome benefit has been a reduction in the risk of stroke, but reductions in myocardial infarction and cardiovascular mortality also have been seen regularly. Elevated...

Dosage and Administration

2 DOSAGE AND ADMINISTRATION Heart Failure: Initiate treatment at 25 mg once daily ( 2.2 ). Hypertension: Initiate treatment at 25 to 100 mg daily in either single or divided doses ( 2.3 ). Edema: Initiate therapy in a hospital setting and titrate slowly. The recommended initial daily dose is 100 mg in single or divided doses ( 2.4 ). Primary hyperaldosteronism: Initiate treatment at 100 to 400 mg in preparation for surgery. In patients unsuitable for surgery use the lowest effective dosage determined for the individual patient ( 2.5 ). 2.1 General Considerations Spironolactone can be taken with or without food, but should be taken consistently with respect to food [see Clinical Pharmacology (12.3) ] . 2.2 Treatment of Heart Failure In patients with serum potassium ≤5.0 mEq/L and eGFR >50 mL/min/1.73 m², initiate treatment at 25 mg once daily. Patients who tolerate 25 mg once daily may have their dosage increased to 50 mg once daily as clinically indicated. Patients who develop hyperkalemia on 25 mg once daily may have their dosage reduced to 25 mg every other day [see Warnings and Precautions (5.1) ] . In patients with an eGFR between 30 and 50 mL/min/1.73 m 2 , consider initiating therapy at 25 mg every other day because of the risk of hyperkalemia [see Use in Specific Populations (8.6) ]. 2.3 Treatment of Essential Hypertension The recommended initial daily dose is 25 to 100 mg of spironolactone administered in either single or divided doses is recommended. Dosage can be titrated at two-week intervals. Doses greater than 100 mg/day generally do not provide additional reductions in blood pressure. 2.4 Treatment of Edema In patients with cirrhosis, initiate therapy in a hospital setting and titrate slowly [see Use in Specific Populations (8.7) ] . The recommended initial daily dosage is 100 mg of spironolactone administered in either single or divided doses, but may range from 25 to 200 mg daily. When given as the sole agent for diuresis, administer for at least five days before increasing dose to obtain desired effect. 2.5 Treatment of Primary Hyperaldosteronism Administer spironolactone in doses of 100 to 400 mg daily in preparation for surgery. For patients who are considered unsuitable for surgery, spironolactone can be used as long-term maintenance therapy at the lowest effective dosage determined for the individual patient.

Side Effects (Adverse Reactions)

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: Hyperkalemia [see Warnings and Precautions (5.1) ] Hypotension and Worsening Renal Function [see Warnings and Precautions (5.2) ] Electrolyte and Metabolic Abnormalities [see Warnings and Precautions (5.3) ] Gynecomastia [see Warnings and Precautions (5.4) ] Impaired neurological function/ coma in patients with hepatic impairment, cirrhosis and ascites [see Use in Specific Populations (8.7) ] The following adverse reactions associated with the use of spironolactone were identified in clinical trials or postmarketing reports. Because these reactions were reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency, reliably, or to establish a causal relationship to drug exposure. Digestive: Gastric bleeding, ulceration, gastritis, diarrhea and cramping, nausea, vomiting. Reproductive: Decreased libido, inability to achieve or maintain erection, irregular menses or amenorrhea, postmenopausal bleeding, breast and nipple pain. Hematologic: Leukopenia (including agranulocytosis), thrombocytopenia. Hypersensitivity: Fever, urticaria, maculopapular or erythematous cutaneous eruptions, anaphylactic reactions, vasculitis. Metabolism: Hyperkalemia, electrolyte disturbances [see Warnings and Precautions (5.1 , 5.3) ] , hyponatremia, hypovolemia. Musculoskeletal : Leg cramps. Nervous system/psychiatric: Lethargy, mental confusion, ataxia, dizziness, headache, drowsiness. Liver/biliary: A very few cases of mixed cholestatic/hepatocellular toxicity, with one reported fatality, have been reported with spironolactone administration. Renal: Renal dysfunction (including renal failure). Skin: Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), drug rash with eosinophilia and systemic symptoms (DRESS), alopecia, pruritis. The most common adverse reaction with spironolactone treatment is gynecomastia ( 5.4 , 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Oxford, at 1-844-508-1455, 8:00 am – 4:30 ET, Monday – Friday or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Drug Interactions

7 DRUG INTERACTIONS Agents increasing serum potassium: Concomitant administration can lead to hyperkalemia ( 5.1 , 7.1 ). Lithium: Increased risk of lithium toxicity ( 7.2 ). NSAIDs: May reduce the diuretic, natriuretic and antihypertensive effect of spironolactone ( 7.3 ). Digoxin: spironolactone can interfere with radioimmunologic assays of digoxin exposure ( 7.4) . Cholestyramine: Hyperkalemic metabolic acidosis has been reported with concomitant use ( 7.5 ). Acetylsalicylic Acid (ASA): ASA may reduce the efficacy of spironolactone ( 7.6 ) Abiraterone: May increase prostate-specific antigen (PSA) levels ( 7.7 ). 7.1 Drugs and Supplements Increasing Serum Potassium Concomitant administration of spironolactone with potassium supplementation or drugs that can increase potassium may lead to severe hyperkalemia. In general, discontinue potassium supplementation in heart failure patients who start spironolactone [see Warnings and Precautions (5.1) and Clinical Pharmacology (12.3) ] . Check serum potassium levels when ACE inhibitor or ARB therapy is altered in patients receiving spironolactone. Examples of drugs that can increase potassium include: ACE inhibitors angiotensin receptor blockers non-steroidal anti-inflammatory drugs (NSAIDs) heparin and low molecular weight heparin trimethoprim 7.2 Lithium Like other diuretics, spironolactone reduces the renal clearance of lithium, thus increasing the risk of lithium toxicity. Monitor lithium levels periodically when spironolactone is coadministered [see Clinical Pharmacology (12.3) ] . 7.3 Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) In some patients, the administration of an NSAID can reduce the diuretic, natriuretic, and antihypertensive effect of diuretics. Therefore, when spironolactone and NSAIDs are used concomitantly, monitor closely to determine if the desired effect of the diuretic is obtained [see Clinical Pharmacology (12.3) ] . 7.4 Digoxin Spironolactone and its metabolites interfere with radioimmunoassays for digoxin and increase the apparent exposure to digoxin. It is unknown to what extent, if any, spironolactone may increase actual digoxin exposure. In patients taking concomitant digoxin, use an assay that does not interact with spironolactone. 7.5 Cholestyramine Hyperkalemic metabolic acidosis has been reported in patients given spironolactone concurrently with cholestyramine. 7.6 Acetylsalicylic Acid Acetylsalicylic acid may reduce the efficacy of spironolactone. Therefore, when spironolactone and acetylsalicylic acid are used concomitantly, spironolactone may need to be titrated to higher maintenance dose and the patient should be observed closely to determine if the desired effect is obtained [see Clinical Pharmacology (12.3) ] . 7.7 Abiraterone Spironolactone binds to the androgen receptor and may increase prostate-specific antigen (PSA) levels in abiraterone-treated prostate cancer patients. Concomitant use of spironolactone and abiraterone is not recommended.

Contraindications

4 CONTRAINDICATIONS Spironolactone is contraindicated in the patients with: Hyperkalemia Addison’s disease Concomitant use of eplerenone Spironolactone is contraindicated in patients with ( 4 ): Hyperkalemia Addison’s disease Concomitant use of eplerenone

Pregnancy and Breastfeeding

8.1 Pregnancy Risk Summary Based on mechanism of action and findings in animal studies, spironolactone may affect sex differentiation of the male during embryogenesis [see Data ] . Rat embryofetal studies report feminization of male fetuses and endocrine dysfunction in females exposed to spironolactone in utero. Limited available data from published case reports and case series did not demonstrate an association of major malformations or other adverse pregnancy outcomes with spironolactone . There are risks to the mother and fetus associated with heart failure, cirrhosis and poorly controlled hypertension during pregnancy [see Clinical Considerations ] . Because of the potential risk to the male fetus due to anti-androgenic properties of spironolactone and animal data, avoid spironolactone in pregnant women or advise a pregnant woman of the potential risk to a male fetus. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2%-4% and 15%-20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Pregnant women with congestive heart failure are at increased risk for preterm birth. Stroke volume and heart rate increase during pregnancy, increasing cardiac output, especially during the first trimester. Clinical classification of heart disease may worsen with pregnancy and lead to maternal death. Closely monitor pregnant patients for destabilization of their heart failure . Pregnant women with symptomatic cirrhosis generally have poor outcomes including hepatic failure, variceal hemorrhage, preterm delivery, fetal growth restriction and maternal death. Outcomes are worse with coexisting esophageal varices. Pregnant women with cirrhosis of the liver...

Overdosage

10 OVERDOSAGE The oral LD 50 of spironolactone is greater than 1000 mg/kg in mice, rats, and rabbits. Acute overdosage of spironolactone may be manifested by drowsiness, mental confusion, maculopapular or erythematous rash, nausea, vomiting, dizziness, or diarrhea. Rarely, instances of hyponatremia, hyperkalemia, or hepatic coma may occur in patients with severe liver disease, but these are unlikely due to acute overdosage. Hyperkalemia may occur, especially in patients with impaired renal function. Treatment: Induce vomiting or evacuate the stomach by lavage. There is no specific antidote. Treatment is supportive to maintain hydration, electrolyte balance, and vital functions. Patients who have renal impairment may develop hyperkalemia. In such cases, discontinue spironolactone.

How Supplied

16 HOW SUPPLIED/STORAGE AND HANDLING Product: 50090-6539 NDC: 50090-6539-0 90 TABLET, COATED in a BOTTLE NDC: 50090-6539-1 30 TABLET, COATED in a BOTTLE

About This Information

This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

What are side effects?

Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

What are drug interactions?

Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.