spironolactone

INDICATIONS AND USAGE Spironolactone tablets are indicated in the management of: Primary hyperaldosteronism for: Establishing the diagnosis of primary hyperaldosteronism by therapeutic trial. Short-term preoperative treatment of patients with primary hyperaldosteronism. Long-term maintenance therapy for patients with discrete aldosterone-producing adrenal adenomas who are judged to be poor operative risks or who decline surgery. Long-term maintenance therapy for patients with bilateral micro or macronodular adrenal hyperplasia (idiopathic hyperaldosteronism). Edematous conditions for patients with: Congestive heart failure: For the management of edema and sodium retention when the patient is only partially responsive to, or is intolerant of, other therapeutic measures. Spironolactone tablets are also indicated for patients with congestive heart failure taking digitalis when other therapies are considered inappropriate. Cirrhosis of the liver accompanied by edema and/or ascites: Aldosterone levels may be exceptionally high in this condition. Spironolactone tablets are indicated for maintenance therapy together with bed rest and the restriction of fluid and sodium. Nephrotic syndrome: For nephrotic patients when treatment of the underlying disease, restriction of fluid and sodium intake, and the use of other diuretics do not provide an adequate response. Essential hypertension Spironolactone tablets are indicated 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. 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 systolic or diastolic pressure causes increased cardiovascular risk, and the absolute risk increase per mmHg is greater at higher blood pressures, so that even modest reductions of severe hypertension can provide substantial benefit. Relative risk reduction from blood pressure reduction is similar across populations with varying absolute risk, so the absolute benefit is greater in patients who are at higher risk independent of their hypertension (for example, patients with diabetes or hyperlipidemia), and such patients would be expected to benefit from more aggressive treatment to a lower blood pressure goal. Some antihypertensive drugs have smaller blood pressure effects (as monotherapy) in black patients, and many antihypertensive drugs have additional approved indications and effects (e.g., on angina, heart failure, or diabetic kidney disease). These considerations may guide selection of therapy. Usually in combination with other drugs, spironolactone tablets are indicated for patients who cannot be treated adequately with other agents or for whom other agents are consider …

DOSAGE AND ADMINISTRATION Primary hyperaldosteronism. Spironolactone tablets may be employed as an initial diagnostic measure to provide presumptive evidence of primary hyperaldosteronism while patients are on normal diets. Long test: Spironolactone tablets are administered at a daily dosage of 400 mg for three to four weeks. Correction of hypokalemia and of hypertension provides presumptive evidence for the diagnosis of primary hyperaldosteronism. Short test: Spironolactone tablets are administered at a daily dosage of 400 mg for four days. If serum potassium increases during spironolactone tablets administration but drops when spironolactone tablets are discontinued, a presumptive diagnosis of primary hyperaldosteronism should be considered. After the diagnosis of hyperaldosteronism has been established by more definitive testing procedures, spironolactone tablets may be administered in doses of 100 to 400 mg daily in preparation for surgery. For patients who are considered unsuitable for surgery, spironolactone tablets may be employed for long-term maintenance therapy at the lowest effective dosage determined for the individual patient. Edema in adults (congestive heart failure, hepatic cirrhosis, or nephrotic syndrome). An initial daily dosage of 100 mg of spironolactone tablets administered in either single or divided doses is recommended, but may range from 25 to 200 mg daily. When given as the sole agent for diuresis, spironolactone tablets should be continued for at least five days at the initial dosage level, after which it may be adjusted to the optimal therapeutic or maintenance level administered in either single or divided daily doses. If, after five days, an adequate diuretic response to spironolactone tablets have not occurred, a second diuretic that acts more proximally in the renal tubule may be added to the regimen. Because of the additive effect of spironolactone tablets when administered concurrently with such diuretics, an enhanced diuresis usually begins on the first day of combined treatment; combined therapy is indicated when more rapid diuresis is desired. The dosage of spironolactone tablets should remain unchanged when other diuretic therapy is added. Essential hypertension. For adults, an initial daily dosage of 50 to 100 mg of spironolactone tablets administered in either single or divided doses is recommended. Spironolactone tablets may also be given with diuretics that act more proximally in the renal tubule or with other antihypertensive agents. Treatment with spironolactone tablets should be continued for at least two weeks since the maximum response may not occur before this time. Subsequently, dosage should be adjusted according to the response of the patient. Hypokalemia. Spironolactone tablets in a dosage ranging from 25 mg to 100 mg daily are useful in treating a diuretic-induced hypokalemia, when oral potassium supplements or other potassium-sparing regimens are considered inappropriate. Severe heart failure in conjunction with standard therapy (NYHA class III - IV). Treatment should be initiated with spironolactone 25 mg once daily if the patient’s serum potassium is ≤5.0 mEq/L and the patient’s serum creatinine is ≤ 2.5 mg/dL. Patients who tolerate 25 mg once daily may have their dosage increased to 50 mg once daily as clinically indicated. Patients who do not tolerate 25 mg once daily may have their dosage reduced to 25 mg every other day. See Warnings: Hyperkalemia in patients with severe heart failure for advice on monitoring serum potassium and serum creatinine.

3 DOSAGE FORMS AND STRENGTHS Spironolactone tablets USP 25 mg are light yellow to yellow colored, round, biconvex, film coated tablets with inscription “AD” on one side and plain on the other side having faint odour of peppermint. Spironolactone tablets USP 50 mg are light orange to orange colored, oval, biconvex, film coated tablets with inscription “AE” on one side and breakline on the other side having faint odour of peppermint. Spironolactone tablets USP 100 mg are light peach to peach colored, round, biconvex, film coated tablets with inscription “AF” on one side and breakline on the other side having faint odour of peppermint. Tablets: 25 mg, 50 mg, and 100 mg ( 3 )

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

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 tablets treatment is gynecomastia ( 5.4 , 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Sun Pharmaceutical Industries, Inc. at 1-800-406-7984 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

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 tablets ( 7.3 ). • Digoxin: Spironolactone tablets 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 tablets ( 7.6 ). • Abiraterone: May increase prostate-specific antigen (PSA) levels ( 7.7 ). • Mitotane: Avoid concomitant use of spironolactone tablets and mitotane ( 7.8 ). 7.1 Drugs and Supplements Increasing Serum Potassium Concomitant administration of spironolactone tablets 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 tablets [ 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 tablets. 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 tablets reduces the renal clearance of lithium, thus increasing the risk of lithium toxicity. Monitor lithium levels periodically when spironolactone tablets are 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 tablets 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 tablets concurrently with cholestyramine. 7.6 Acetylsalicylic Acid Acetylsalicylic acid may reduce the efficacy of spironolactone. Therefore, when spironolactone tablets and acetylsalicylic acid are used concomitantly, spironolactone tablets 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. 7.8 Mitotane Avoid concomitant use of spironolactone tablets and mitotane. Spironolactone reduces mitotane plasma levels [ see Clinical Pharmacology (12.3) ] .

8 USE IN SPECIFIC POPULATIONS • Pregnancy: Based on animal data, spironolactone tablets may affect sex differentiation of the male during embryogenesis ( 8.1 ). 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 should be carefully monitored and managed accordingly. Hypertension in pregnancy increases the maternal risk for pre-eclampsia, gestational diabetes, premature delivery, and delivery complications (e.g., need for cesarean section, and post-partum hemorrhage). Hypertension increases the fetal risk for intrauterine growth restriction and intrauterine death. Data Animal Data Teratology studies with spironolactone tablets have been carried out in mice and rabbits at doses of up to 20 mg/kg/day. On a body surface area basis, this dose in the mouse is substantially below the maximum recommended human dose and, in the rabbit, approximates the maximum recommended human dose. No teratogenic or other embryotoxic effects were observed in mice, but the 20 mg/kg dose caused an increased rate of resorption and a lower number of live fetuses in rabbits. Because of its antiandrogenic activity and the requirement of testosterone for male morphogenesis, spironolactone tablets may have the potential for adversely affecting sex differentiation of the male during embryogenesis. When administered to rats at 200 mg/kg/day between gestation days 13 and 21 (late embryogenesis and fetal development), feminization of male fetuses was observed. Offspring exposed during late pregnancy to 50 and 100 mg/kg/day doses of spironolactone tablets exhibited changes in the reproductive tract including dose-dependent decreases in weights of the ventral prostate and seminal vesicle in males, ovaries and uteri that were enlarged in females, and other indications of endocrine dysfunction, that persisted into adulthood. Spironolactone tablets has known endocrine effects in animals including progestational and antiandrogenic effects. 8.2 Lactation Risk Summary Spironolactone is not present in breastmilk; however, limited data from a lactating woman at 17 d …

12.1 Mechanism of Action Spironolactone and its active metabolites are specific pharmacologic antagonists of aldosterone, acting primarily through competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted renal tubule. Spironolactone causes increased amounts of sodium and water to be excreted, while potassium is retained. Spironolactone acts both as a diuretic and as an antihypertensive drug by this mechanism. It may be given alone or with other diuretic agents that act more proximally in the renal tubule.

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, USP is practically insoluble in water, soluble in alcohol, and freely soluble in benzene and in chloroform. Spironolactone tablets, 25 mg contain the following inactive ingredients: anhydrous lactose, colloidal silicon dioxide, docusate sodium 85%/sodium benzoate 15%, entrapped peppermint flavor, magnesium stearate, microcrystalline cellulose, povidone, and sodium starch glycolate. Spironolactone tablets, 50 mg and 100 mg contain the following inactive ingredients: anhydrous lactose, carnauba wax, colloidal silicon dioxide, docusate sodium 85%/sodium benzoate 15%, entrapped peppermint flavor, hypromellose, magnesium stearate, microcrystalline cellulose, polydextrose, polyethylene glycol, povidone, sodium starch glycolate, titanium dioxide, and triacetin. structure

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 spironolactone-induced hyperkalemia. In such cases, spironolactone should be discontinued immediately. With severe hyperkalemia, the clinical situation dictates the procedures to be employed. These may include the intravenous administration of calcium chloride solution, sodium bicarbonate solution and/or the oral or parenteral administration of glucose with a rapid-acting insulin preparation. These are temporary measures to be repeated as required. Cationic exchange resins such as sodium polystyrene sulfonate may be orally or rectally administered. Persistent hyperkalemia may require dialysis.

16 HOW SUPPLIED/STORAGE AND HANDLING Spironolactone Tablets USP, 25 mg are white to off-white, round, biconvex, film-coated tablets debossed with '660' on one side and plain on the other side and are supplied as follows: NDC 70771-1027-3 in bottles of 30 tablets with child-resistant closure NDC 70771-1027-9 in bottles of 90 tablets with child-resistant closure NDC 70771-1027-1 in bottles of 100 tablets with child-resistant closure NDC 70771-1027-5 in bottles of 500 tablets NDC 70771-1027-0 in bottles of 1000 tablets NDC 70771-1027-4 in unit-dose blister cartons of 100 (10 x 10) unit-dose tablets Spironolactone Tablets USP, 50 mg are white to off-white, oval shaped, biconvex, film-coated tablets debossed with '661' on the scored side and plain on the other side and are supplied as follows: NDC 70771-1028-3 in bottles of 30 tablets with child-resistant closure NDC 70771-1028-9 in bottles of 90 tablets with child-resistant closure NDC 70771-1028-1 in bottles of 100 tablets with child-resistant closure NDC 70771-1028-5 in bottles of 500 tablets NDC 70771-1028-0 in bottles of 1000 tablets NDC 70771-1028-4 in unit-dose blister cartons of 100 (10 x 10) unit-dose tablets Spironolactone Tablets USP, 100 mg are white to off-white, round, biconvex, film-coated tablets debossed with '662' on one side and scored on the other side and are supplied as follows: NDC 70771-1029-3 in bottles of 30 tablets with child-resistant closure NDC 70771-1029-9 in bottles of 90 tablets with child-resistant closure NDC 70771-1029-1 in bottles of 100 tablets with child-resistant closure NDC 70771-1029-5 in bottles of 500 tablets NDC 70771-1029-0 in bottles of 1000 tablets NDC 70771-1029-4 in unit-dose blister cartons of 100 (10 x 10) unit-dose tablets Storage Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature] . Protect from light. Dispense in a tight, light-resistant container (USP).