Interpril

Hypertension

Interpril is indicated for the treatment of hypertension in adult patients and pediatric patients 6 years of age and older to lower blood pressure. Lowering blood pressure lowers 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 1 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.

Interpril may be administered alone or with other antihypertensive agents.

Heart Failure

Interpril is indicated to reduce signs and symptoms of systolic heart failure.

Reduction Of Mortality In Acute Myocardial Infarction

Interpril is indicated for the reduction of mortality in treatment of hemodynamically stable patients within 24 hours of acute myocardial infarction. Patients should receive, as appropriate, the standard recommended treatments such as thrombolytics, aspirin and beta-blockers.

Hypertension

Interpril is indicated for the treatment of hypertension in adult patients and pediatric patients 6 years of age and older to lower blood pressure. Lowering blood pressure lowers the risk of fatal and non-fatal 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 1 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.

Interpril may be administered alone or with other antihypertensive agents.

Heart Failure

Interpril is indicated to reduce signs and symptoms of heart failure in patients who are not responding adequately to diuretics and digitalis.

Acute Myocardial Infarction

Interpril is indicated for the reduction of mortality in treatment of hemodynamically stable patients within 24 hours of acute myocardial infarction. Patients should receive, as appropriate, the standard recommended treatments such as thrombolytics, aspirin and beta-blockers.

Hypertension

Adults

Initial Therapy in adults: The recommended initial dose is 10 mg taken orally once a day. Adjust dosage as needed according to blood pressure response. The usual dosage range is 20 to 40 mg per day administered in a single daily dose. Doses up to 80 mg per day have been used but do not appear to give greater effect.

Use With Diuretics In Adults

If blood pressure is not controlled with Interpril alone, a low dose of a diuretic may be added (e.g., hydrochlorothiazide, 12.5 mg). After the addition of a diuretic, it may be possible to reduce the dose of Interpril.

The recommended starting dose in adult patients with hypertension taking diuretics is 5 mg once per day.

Pediatric Patients 6 Years Of Age And Older With Hypertension

For pediatric patients with glomerular filtration rate > 30 mL/min/1.73m², the recommended starting dose is 0.07 mg per kg (up to 5 mg total) taken orally once daily. Dosage should be adjusted according to blood pressure response up to a maximum of 0.61 mg per kg (up to 40 mg) once daily. Doses above 0.61 mg per kg (or in excess of 40 mg) have not been studied in pediatric patients.

Interpril is not recommended in pediatric patients less than 6 years of age or in pediatric patients with glomerular filtration rate < 30 mL/min/1.73m².

Heart Failure

The recommended starting dose for Interpril, when used with diuretics and (usually) digitalis as adjunctive therapy for systolic heart failure, is 5 mg taken orally once daily. The recommended starting dose in these patients with hyponatremia (serum sodium < 130 mEq/L) is 2.5 mg once daily. Increase as tolerated to a maximum of 40 mg once daily.

Diuretic dose may need to be adjusted to help minimize hypovolemia, which may contribute to hypotension. The appearance of hypotension after the initial dose of Interpril does not preclude subsequent careful dose titration with the drug, following effective management of the hypotension.

Reduction Of Mortality In Acute Myocardial Infarction

Initiation

In hemodynamically stable patients within 24 hours of the onset of symptoms of acute myocardial infarction, give Interpril 5 mg orally, followed by 5 mg after 24 hours, and then 10 mg once daily. Dosing should continue for at least six weeks. In patients with a low systolic blood pressure (≤ 120 mmHg and > 100 mmHg) during the first 3 days after the infarct initiate therapy with 2.5 mg once daily and titrate up based on tolerability.

Maintenance

The usual maintenance dose is 10 mg once daily. If hypotension (systolic blood pressure ≤ 100 mmHg) occurs during maintenance treatment, give 5 mg once daily with temporary reductions to 2.5 mg if needed. If prolonged hypotension occurs (systolic blood pressure < 90 mmHg for more than 1 hour) Interpril should be withdrawn.

Dose In Patients With Renal Impairment

No dose adjustment of Interpril is required in patients with creatinine clearance > 30 mL/min.

In patients with creatinine clearance ≥ 10 mL/min and ≤ 30 mL/min, reduce the initial dose of Interpril to half of the usual recommended dose, i.e., hypertension, 5 mg once daily; systolic heart failure, 2.5 mg once daily and acute myocardial infarction, 2.5 mg once daily. Up titrate as tolerated to a maximum of 40 mg daily. For patients on hemodialysis or creatinine clearance < 10 mL/min, the recommended initial dose is 2.5 mg once daily.

Hypertension

Initial therapy in adults: The recommended initial dose is 10 mg once a day. Adjust dosage according to blood pressure response. The usual dosage range is 20 to 40 mg per day administered in a single daily dose. Doses up to 80 mg have been used but do not appear to give a greater effect.

Use With Diuretics In Adults

If blood pressure is not controlled with Interpril alone, a low dose of a diuretic may be added (e.g., hydrochlorothiazide 12.5 mg).

The recommended starting dose in adult patients with hypertension taking diuretics is 5 mg once per day.

Pediatric Patients 6 Years Of Age And Older With Hypertension

For pediatric patients with glomerular filtration rate >30 mL/min/1.73 m², the recommended starting dose is 0.07 mg/kg once daily (up to 5 mg total). Dosage should be adjusted according to blood pressure response up to a maximum of 0.61 mg/kg (up to 40 mg) once daily. Doses above 0.61 mg/kg (or in excess of 40 mg) have not been studied in pediatric patients.

Interpril is not recommended in pediatric patients <6 years or in pediatric patients with glomerular filtration rate <30 mL/min/1.73 m².

Heart Failure

The recommended starting dose for Interpril, when used with diuretics and (usually) digitalis as adjunctive therapy is 5 mg once daily. The recommended starting dose in these patients with hyponatremia (serum sodium <130 mEq/L) is 2.5 mg once daily. Increase as tolerated to a maximum of 40 mg once daily.

Diuretic dose may need to be adjusted to help minimize hypovolemia, which may contribute to hypotension. The appearance of hypotension after the initial dose of Interpril does not preclude subsequent careful dose titration with the drug, following effective management of the hypotension.

Acute Myocardial Infarction

In hemodynamically stable patients within 24 hours of the onset of symptoms of acute myocardial infarction, give Interpril 5 mg orally, followed by 5 mg after 24 hours, 10 mg after 48 hours and then 10 mg once daily. Dosing should continue for at least 6 weeks.

Initiate therapy with 2.5 mg in patients with a low systolic blood pressure (100-120 mmHg) during the first 3 days after the infarct. If hypotension occurs (systolic blood pressure ≤100 mmHg) consider doses of 2.5 or 5 mg. If prolonged hypotension occurs (systolic blood pressure <90 mmHg for more than 1 hour) discontinue Interpril.

Dose In Patients With Renal Impairment

No dose adjustment of Interpril is required in patients with creatinine clearance >30 mL/min. In patients with creatinine clearance 10-30 mL/min, reduce the initial dose of Interpril to half of the usual recommended dose (i.e., hypertension, 5 mg; heart failure or acute MI, 2.5 mg). For patients on hemodialysis or creatinine clearance <10 mL/min, the recommended initial dose is 2.5 mg once daily.

Preparation Of Suspension

To make 200 mL of a suspension at 1.0 mg/mL, add 10 mL of Purified Water USP to a polyethylene terephthalate (PET) bottle containing ten 20-mg tablets of Interpril and shake for at least one minute.

Add 30 mL of Sodium Citrate and Citric Acid Oral Solution or Cytra-2 diluent and 160 mL of Ora-Sweet SF™ to the concentrate in the PET bottle and gently shake for several seconds to disperse the ingredients. The suspension should be stored at or below 25°C (77°F) and can be stored for up to four weeks. Shake the suspension before each use.

Interpril is contraindicated in patients with:

• a history of angioedema or hypersensitivity related to previous treatment with an angiotensin converting enzyme inhibitor
• hereditary or idiopathic angioedema

Do not co-administer aliskiren with Interpril in patients with diabetes.

Interpril is contraindicated in combination with a neprilysin inhibitor (e.g., sacubitril). Do not administer Interpril within 36 hours of switching to or from sacubitril/valsartan, a neprilysin inhibitor.

Interpril is contraindicated in patients with:

• a history of angioedema or hypersensitivity related to previous treatment with an angiotensin converting enzyme inhibitor
• hereditary or idiopathic angioedema.

Do not coadminister aliskiren with Interpril in patients with diabetes. Interpril is contraindicated in combination with a neprilysin inhibitor (e.g., sacubitril). Do not administer Interpril within 36 hours of switching to or from sacubitril/valsartan, a product containing a neprilysin inhibitor.

WARNINGS

Included as part of the PRECAUTIONS section.

PRECAUTIONS

Fetal Toxicity

Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue Interpril as soon as possible.

Angioedema And Anaphylactoid Reactions

Angioedema

Head and Neck Angioedema

Angioedema of the face, extremities, lips, tongue, glottis and/or larynx, including some fatal reactions, have occurred in patients treated with angiotensin converting enzyme inhibitors, including lisinopril, at any time during treatment. Patients with involvement of the tongue, glottis or larynx are likely to experience airway obstruction, especially those with a history of airway surgery. Interpril should be promptly discontinued and appropriate therapy and monitoring should be provided until complete and sustained resolution of signs and symptoms of angioedema has occurred.

Patients with a history of angioedema unrelated to ACE inhibitor therapy may be at increased risk of angioedema while receiving an ACE inhibitor. ACE inhibitors have been associated with a higher rate of angioedema in Black than in non-Black patients.

Patients receiving coadministration of an ACE inhibitor and mTOR (mammalian target of rapamycin) inhibitor (e.g., temsirolimus, sirolimus, everolimus) therapy or a neprilysin inhibitor may be at increased risk for angioedema.

Intestinal Angioedema

Intestinal angioedema has occurred in patients treated with ACE inhibitors. These patients presented with abdominal pain (with or without nausea or vomiting); in some cases there was no prior history of facial angioedema and C-1 esterase levels were normal. In some cases, the angioedema was diagnosed by procedures including abdominal CT scan or ultrasound, or at surgery, and symptoms resolved after stopping the ACE inhibitor.

Anaphylactoid Reactions

Anaphylactoid Reactions During Desensitization

Two patients undergoing desensitizing treatment with hymenoptera venom while receiving ACE inhibitors sustained life-threatening anaphylactoid reactions.

Anaphylactoid Reactions During Dialysis

Sudden and potentially life threatening anaphylactoid reactions have occurred in some patients dialyzed with high-flux membranes and treated concomitantly with an ACE inhibitor. In such patients, dialysis must be stopped immediately, and aggressive therapy for anaphylactoid reactions must be initiated. Symptoms have not been relieved by antihistamines in these situations. In these patients, consideration should be given to using a different type of dialysis membrane or a different class of antihypertensive agent. Anaphylactoid reactions have also been reported in patients undergoing low-density lipoprotein apheresis with dextran sulfate absorption.

Impaired Renal Function

Monitor renal function periodically in patients treated with Interpril. Changes in renal function including acute renal failure can be caused by drugs that inhibit the renin-angiotensin system. Patients whose renal function may depend in part on the activity of the reninangiotensin system (e.g., patients with renal artery stenosis, chronic kidney disease, severe congestive heart failure, post-myocardial infarction or volume depletion) may be at particular risk of developing acute renal failure on Interpril. Consider withholding or discontinuing therapy in patients who develop a clinically significant decrease in renal function on Interpril.

Hypotension

Interpril can cause symptomatic hypotension, sometimes complicated by oliguria, progressive azotemia, acute renal failure or death. Patients at risk of excessive hypotension include those with the following conditions or characteristics: heart failure with systolic blood pressure below 100 mmHg, ischemic heart disease, cerebrovascular disease, hyponatremia, high dose diuretic therapy, renal dialysis, or severe volume and/or salt depletion of any etiology.

In these patients, Interpril should be started under very close medical supervision and such patients should be followed closely for the first two weeks of treatment and whenever the dose of Interpril and/or diuretic is increased. Avoid use of Interpril in patients who are hemodynamically unstable after acute MI.

Symptomatic hypotension is also possible in patients with severe aortic stenosis or hypertrophic cardiomyopathy.

Surgery/Anesthesia

In patients undergoing major surgery or during anesthesia with agents that produce hypotension, Interpril may block angiotensin II formation secondary to compensatory renin release. If hypotension occurs and is considered to be due to this mechanism, it can be corrected by volume expansion.

Hyperkalemia

Serum potassium should be monitored periodically in patients receiving Interpril. Drugs that inhibit the renin-angiotensin system can cause hyperkalemia. Risk factors for the development of hyperkalemia include renal insufficiency, diabetes mellitus, and the concomitant use of potassium-sparing diuretics, potassium supplements and/or potassium-containing salt substitutes.

Hepatic Failure

ACE inhibitors have been associated with a syndrome that starts with cholestatic jaundice or hepatitis and progresses to fulminant hepatic necrosis and sometimes death. The mechanism of this syndrome is not understood. Patients receiving ACE inhibitors who develop jaundice or marked elevations of hepatic enzymes should discontinue the ACE inhibitor and receive appropriate medical treatment.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment Of Fertility

There was no evidence of a tumorigenic effect when lisinopril was administered for 105 weeks to male and female rats at doses up to 90 mg per kg per day (about 56 or 9 times* the maximum recommended daily human dose, based on body weight and body surface area, respectively). There was no evidence of carcinogenicity when lisinopril was administered for 92 weeks to (male and female) mice at doses up to 135 mg per kg per day (about 84 times* the maximum recommended daily human dose). This dose was 6.8 times the maximum human dose based on body surface area in mice.

Lisinopril was not mutagenic in the Ames microbial mutagen test with or without metabolic activation. It was also negative in a forward mutation assay using Chinese hamster lung cells. Lisinopril did not produce single strand DNA breaks in an in vitro alkaline elution rat hepatocyte assay. In addition, lisinopril did not produce increases in chromosomal aberrations in an in vitro test in Chinese hamster ovary cells or in an in vivo study in mouse bone marrow.

There were no adverse effects on reproductive performance in male and female rats treated with up to 300 mg per kg per day of lisinopril. This dose is 188 times and 30 times the maximum human dose when based on mg/kg and mg/m², respectively.

Studies in rats indicate that lisinopril crosses the blood brain barrier poorly. Multiple doses of lisinopril in rats do not result in accumulation in any tissues. Milk of lactating rats contains radioactivity following administration of 14C lisinopril. By whole body autoradiography, radioactivity was found in the placenta following administration of labeled drug to pregnant rats, but none was found in the fetuses.

*Calculations assume a human weight of 50 kg and human body surface area of 1.62m².

Use In Specific Populations

Pregnancy

Risk Summary

Interpril can cause fetal harm when administered to a pregnant woman. Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Most epidemiologic studies examining fetal abnormalities after exposure to antihypertensive use in the first trimester have not distinguished drugs affecting the renin-angiotensin system from other antihypertensive agents. When pregnancy is detected, discontinue Interpril as soon as possible.

The estimated background risk of major birth defects and miscarriage for the indicated population(s) are unknown. In the general U.S. 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

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. Pregnant women with hypertension should be carefully monitored and managed accordingly.

Fetal/Neonatal Adverse Reactions

Oligohydramnios in pregnant women who use drugs affecting the renin-angiotensin system in the second and third trimesters of pregnancy can result in the following: reduced fetal renal function leading to anuria and renal failure, fetal lung hypoplasia and skeletal deformations, including skull hypoplasia, hypotension, and death. In the unusual case that there is no appropriate alternative to therapy with drugs affecting the renin-angiotensin system for a particular patient, apprise the mother of the potential risk to the fetus.

Perform serial ultrasound examinations to assess the intra-amniotic environment. Fetal testing may be appropriate, based on the week of pregnancy. Patients and physicians should be aware, however, that oligohydramnios may not appear until after the fetus has sustained irreversible injury. Closely observe infants with histories of in utero exposure to Interpril for hypotension, oliguria, and hyperkalemia. If oliguria or hypotension occur in neonates with a history of in utero exposure to Interpril, support blood pressure and renal perfusion. Exchange transfusions or dialysis may be required as a means of reversing hypotension and substituting for disordered renal function.

Lactation

Risk Summary

No data are available regarding the presence of lisinopril in human milk or the effects of lisinopril on the breastfed infant or on milk production. Lisinopril is present in rat milk. Because of the potential for severe adverse reactions in the breastfed infant, advise women not to breastfeed during treatment with Interpril.

Pediatric Use

Antihypertensive effects and safety of lisinopril have been established in pediatric patients aged 6 to 16 years. No relevant differences between the adverse reaction profile for pediatric patients and adult patients were identified.

Safety and effectiveness of lisinopril have not been established in pediatric patients under the age 6 or in pediatric patients with glomerular filtration rate < 30 mL/min/1.73 m².

Neonates With A History Of In Utero Exposure To Interpril

If oliguria or hypotension occurs, direct attention toward support of blood pressure and renal perfusion. Exchange transfusions or dialysis may be required as a means of reversing hypotension and/or substituting for disordered renal function.

Geriatric Use

No dosage adjustment with Interpril is necessary in elderly patients. In a clinical study of lisinopril in patients with myocardial infarctions (GISSI-3 Trial), 4,413 (47%) were 65 and over, while 1,656 (18%) were 75 and over. In this study, 4.8 % of patients aged 75 years and older discontinued lisinopril treatment because of renal dysfunction vs. 1.3% of patients younger than 75 years. No other differences in safety or effectiveness were observed between elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

Race

ACE inhibitors, including Interpril, have an effect on blood pressure that is less in Black patients than in non-Blacks.

Renal Impairment

Dose adjustment of Interpril is required in patients undergoing hemodialysis or whose creatinine clearance is ≤ 30 mL/min. No dose adjustment of Interpril is required in patients with creatinine clearance > 30 mL/min.

WARNINGS

Included as part of the "PRECAUTIONS" Section

PRECAUTIONS

Fetal Toxicity

Pregnancy Category D

Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue Interpril as soon as possible.

Angioedema And Anaphylactoid Reactions

Angioedema

Head and Neck Angioedema

Angioedema of the face, extremities, lips, tongue, glottis and/or larynx, including some fatal reactions, have occurred in patients treated with angiotensin converting enzyme inhibitors, including Interpril, at any time during treatment. Patients with involvement of the tongue, glottis or larynx are likely to experience airway obstruction, especially those with a history of airway surgery. Interpril should be promptly discontinued and appropriate therapy and monitoring should be provided until complete and sustained resolution of signs and symptoms of angioedema has occurred.

Patients with a history of angioedema unrelated to ACE inhibitor therapy may be at increased risk of angioedema while receiving an ACE inhibitor. ACE inhibitors have been associated with a higher rate of angioedema in Black than in non-Black patients.

Patients receiving concomitant ACE inhibitor and mTOR (mammalian target of rapamycin) inhibitor (e.g., temsirolimus, sirolimus, everolimus) therapy may be at increased risk for angioedema.

Patients receiving concomitant ACE inhibitor and neprilysin inhibitor therapy may be at increased risk for angioedema.

Intestinal Angioedema

Intestinal angioedema has occurred in patients treated with ACE inhibitors. These patients presented with abdominal pain (with or without nausea or vomiting); in some cases there was no prior history of facial angioedema and C-1 esterase levels were normal. In some cases, the angioedema was diagnosed by procedures including abdominal CT scan or ultrasound, or at surgery, and symptoms resolved after stopping the ACE inhibitor.

Anaphylactoid Reactions

Anaphylactoid Reactions During Desensitization

Two patients undergoing desensitizing treatment with Hymenoptera venom while receiving ACE inhibitors sustained life-threatening anaphylactoid reactions.

Anaphylactoid Reactions During Dialysis

Sudden and potentially life-threatening anaphylactoid reactions have occurred in some patients dialyzed with high-flux membranes and treated concomitantly with an ACE inhibitor. In such patients, dialysis must be stopped immediately, and aggressive therapy for anaphylactoid reactions must be initiated. Symptoms have not been relieved by antihistamines in these situations. In these patients, consideration should be given to using a different type of dialysis membrane or a different class of antihypertensive agent. Anaphylactoid reactions have also been reported in patients undergoing low-density lipoprotein apheresis with dextran sulfate absorption.

Impaired Renal Function

Monitor renal function periodically in patients treated with Interpril. Changes in renal function including acute renal failure can be caused by drugs that inhibit the renin-angiotensin system. Patients whose renal function may depend in part on the activity of the renin-angiotensin system (e.g., patients with renal artery stenosis, chronic kidney disease, severe congestive heart failure, post-myocardial infarction or volume depletion) may be at particular risk of developing acute renal failure on Interpril. Consider withholding or discontinuing therapy in patients who develop a clinically significant decrease in renal function on Interpril.

Hypotension

Interpril can cause symptomatic hypotension, sometimes complicated by oliguria, progressive azotemia, acute renal failure or death. Patients at risk of excessive hypotension include those with the following conditions or characteristics: heart failure with systolic blood pressure below 100 mmHg, ischemic heart disease, cerebrovascular disease, hyponatremia, high dose diuretic therapy, renal dialysis, or severe volume and/or salt depletion of any etiology.

In these patients, start Interpril under medical supervision and follow such patients for the first two weeks of treatment and whenever the dose of Interpril and/or diuretic is increased. Avoid use of Interpril in patients who are hemodynamically unstable after acute MI.

Symptomatic hypotension is also possible in patients with severe aortic stenosis or hypertrophic cardiomyopathy.

Surgery/Anesthesia

In patients undergoing major surgery or during anesthesia with agents that produce hypotension, Interpril may block angiotensin II formation secondary to compensatory renin release. If hypotension occurs and is considered to be due to this mechanism, it can be corrected by volume expansion.

Hyperkalemia

Monitor serum potassium periodically in patients receiving Interpril. Drugs that inhibit the reninangiotensin system can cause hyperkalemia. Risk factors for the development of hyperkalemia include renal insufficiency, diabetes mellitus, and the concomitant use of potassium-sparing diuretics, potassium supplements and/or potassium-containing salt substitutes.

Hepatic Failure

ACE inhibitors have been associated with a syndrome that starts with cholestatic jaundice or hepatitis and progresses to fulminant hepatic necrosis and sometimes death. The mechanism of this syndrome is not understood. Patients receiving ACE inhibitors who develop jaundice or marked elevations of hepatic enzymes should discontinue the ACE inhibitor and receive appropriate medical treatment.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment Of Fertility

There was no evidence of a tumorigenic effect when lisinopril was administered for 105 weeks to male and female rats at doses up to 90 mg per kg per day or for 92 weeks to male and female mice at doses up to 135 mg per kg per day. These doses are 10 times and 7 times, respectively, the MRHDD when compared on a body surface area basis.

Lisinopril was not mutagenic in the Ames microbial mutagen test with or without metabolic activation. It was also negative in a forward mutation assay using Chinese hamster lung cells. Lisinopril did not produce single strand DNA breaks in an in vitro alkaline elution rat hepatocyte assay. In addition, lisinopril did not produce increases in chromosomal aberrations in an in vitro test in Chinese hamster ovary cells or in an in vivo study in mouse bone marrow.

There were no adverse effects on reproductive performance in male and female rats treated with up to 300 mg/kg/day of lisinopril (33 times the MRHDD when compared on a body surface area basis).

Studies in rats indicate that lisinopril crosses the blood brain barrier poorly. Multiple doses of lisinopril in rats do not result in accumulation in any tissues. Milk of lactating rats contains radioactivity following administration of ¹⁴C lisinopril. By whole body autoradiography, radioactivity was found in the placenta following administration of labeled drug to pregnant rats, but none was found in the fetuses.

Use In Specific Populations

Pregnancy

Pregnancy Category D

Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue Interpril as soon as possible. These adverse outcomes are usually associated with the use of these drugs in the second and third trimester of pregnancy. Most epidemiologic studies examining fetal abnormalities after exposure to antihypertensive use in the first trimester have not distinguished drugs affecting the renin-angiotensin system from other antihypertensive agents. Appropriate management of maternal hypertension during pregnancy is important to optimize outcomes for both mother and fetus.

In the unusual case that there is no appropriate alternative therapy to drugs affecting the reninangiotensin system for a particular patient, apprise the mother of the potential risk to the fetus. Perform serial ultrasound examinations to assess the intra-amniotic environment. If oligohydramnios is observed, discontinue Interpril, unless it is considered lifesaving for the mother. Fetal testing may be appropriate, based on the week of pregnancy. Patients and physicians should be aware, however, that oligohydramnios may not appear until after the fetus has sustained irreversible injury. Closely observe infants with histories of in utero exposure to Interpril for hypotension, oliguria, and hyperkalemia.

Nursing Mothers

Milk of lactating rats contains radioactivity following administration of ¹⁴C lisinopril. It is not known whether this drug is secreted in human milk. Because many drugs are secreted in human milk, and because of the potential for serious adverse reactions in nursing infants from ACE inhibitors, discontinue nursing or discontinue Interpril.

Pediatric Use

Antihypertensive effects and safety of Interpril have been established in pediatric patients aged 6 to 16 years. No relevant differences between the adverse reaction profile for pediatric patients and adult patients were identified.

Safety and effectiveness of Interpril have not been established in pediatric patients under the age of 6 or in pediatric patients with glomerular filtration rate <30 mL/min/1.73 m².

Neonates With A History Of In Utero Exposure To Interpril

If oliguria or hypotension occurs, direct attention toward support of blood pressure and renal perfusion.

Exchange transfusions or dialysis may be required as a means of reversing hypotension and/or substituting for disordered renal function.

Geriatric Use

No dosage adjustment with Interpril is necessary in elderly patients. In a clinical study of Interpril in patients with myocardial infarctions (GISSI-3 Trial) 4,413 (47%) were 65 and over, while 1,656 (18%) were 75 and over. In this study, 4.8% of patients aged 75 years and older discontinued Interpril treatment because of renal dysfunction vs. 1.3% of patients younger than 75 years. No other differences in safety or effectiveness were observed between elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

Race

ACE inhibitors, including Interpril, have an effect on blood pressure that is less in Black patients than in non-Blacks.

Renal Impairment

Dose adjustment of Interpril is required in patients undergoing hemodialysis or whose creatinine clearance is ≤30 mL/min. No dose adjustment of Interpril is required in patients with creatinine clearance >30 mL/min.

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice.

Hypertension

In clinical trials in patients with hypertension treated with lisinopril, 5.7% of patients on lisinopril discontinued with adverse reactions.

The following adverse reactions (events 2% greater on lisinopril than on placebo) were observed with lisinopril alone: headache (by 3.8%), dizziness (by 3.5%), and cough (by 2.5%).

Heart Failure

In patients with systolic heart failure treated with lisinopril for up to four years, 11% discontinued therapy with adverse reactions. In controlled studies in patients with heart failure, therapy was discontinued in 8.1% of patients treated with lisinopril for 12 weeks, compared to 7.7% of patients treated with placebo for 12 weeks.

The following adverse reactions (events 2% greater on lisinopril than on placebo) were observed with lisinopril: hypotension (by 3.8%), and chest pain (by 2.1%).

In the two-dose ATLAS trial in heart failure patients, withdrawals due to adverse reactions were not different between the low and high dose groups, either in total number of discontinuation (17-18%) or in rare specific reactions (< 1%). The following adverse reactions, mostly related to ACE inhibition, were reported more commonly in the high dose group:

Table 1: Dose-related Adverse Drug Reactions: ATLAS trial

Acute Myocardial Infarction

Patients treated with lisinopril had a higher incidence of hypotension (by 5.3%) and renal dysfunction (by 1.3%) compared with patients not taking lisinopril. Other clinical adverse reactions occurring in 1% or higher of patients with hypertension or heart failure treated with lisinopril in controlled clinical trials and do not appear in other sections of labeling are listed below:

Body as a whole: Fatigue, asthenia, orthostatic effects.

Digestive: Pancreatitis, constipation, flatulence, dry mouth, diarrhea.

Hematologic: Rare cases of bone marrow depression, hemolytic anemia, leukopenia/neutropenia and thrombocytopenia.

Endocrine: Diabetes mellitus, inappropriate antidiuretic hormone secretion.

Metabolic: Gout. Skin: Urticaria, alopecia, photosensitivity, erythema, flushing, diaphoresis, cutaneous pseudolymphoma, toxic epidermal necrolysis, Stevens -Johnson syndrome, and pruritus.

Special Senses: Visual loss, diplopia, blurred vision, tinnitus, photophobia, taste disturbances, olfactory disturbance.

Urogenital: Impotence.

Miscellaneous: A symptom complex has been reported which may include a positive ANA, an elevated erythrocyte sedimentation rate, arthralgia/arthritis, myalgia, fever, vasculitis, eosinophilia, leukocytosis, paresthesia and vertigo. Rash, photosensitivity or other dermatological manifestations may occur alone or in combination with these symptoms.

Clinical Laboratory Test Findings

Serum Potassium

In clinical trials hyperkalemia (serum potassium greater than 5.7 mEq/L) occurred in 2.2% and 4.8% of lisinopril-treated patients with hypertension and heart failure, respectively.

Creatinine, Blood Urea Nitrogen

Minor increases in blood urea nitrogen and serum creatinine, reversible upon discontinuation of therapy, were observed in about 2% of patients with hypertension treated with lisinopril alone. Increases were more common in patients receiving concomitant diuretics and in patients with renal artery stenosis. Reversible minor increases in blood urea nitrogen and serum creatinine were observed in 11.6% of patients with heart failure on concomitant diuretic therapy. Frequently, these abnormalities resolved when the dosage of the diuretic was decreased.

Patients with acute myocardial infarction in the GISSI-3 trial treated with lisinopril had a higher (2.4% versus 1.1% in placebo) incidence of renal dysfunction in-hospital and at six weeks (increasing creatinine concentration to over 3 mg/dL or a doubling or more of the baseline serum creatinine concentration).

Hemoglobin And Hematocrit

Small decreases in hemoglobin and hematocrit (mean decreases of approximately 0.4 g% and 1.3 vol%, respectively) occurred frequently in patients treated with lisinopril but were rarely of clinical importance in patients without some other cause of anemia. In clinical trials, less than 0.1% of patients discontinued therapy due to anemia.

Post-marketing Experience

The following adverse reactions have been identified during post-approval use of lisinopril that are not included in other sections of labeling. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Other reactions include:

Metabolism And Nutrition Disorders

Hyponatremia , cases of hypoglycemia in diabetic patients on oral antidiabetic agents or insulin.

Nervous System And Psychiatric Disorders

Mood alterations (including depressive symptoms), mental confusion, hallucinations

Skin And Subcutaneous Tissue Disorders

Psoriasis

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice.

Hypertension

The following adverse reactions (events 2% greater on Interpril than on placebo) were observed with Interpril vs placebo: headache (5.7% vs 1.9%), dizziness (5.4% vs 1.9%), cough (3.5% vs 1.0%).

Heart Failure

In controlled studies in patients with heart failure, therapy was discontinued in 8.1% of patients treated with Interpril for 12 weeks, compared to 7.7% of patients treated with placebo for 12 weeks.

The following adverse reactions (events 2% greater on Interpril than on placebo) were observed with Interpril vs placebo: hypotension (4.4% vs 0.6%), chest pain (3.4% vs 1.3%).

In the ATLAS trial in heart failure patients, withdrawals for adverse reactions were similar in the low-and high-dose groups. The following adverse reactions, mostly related to ACE inhibition, were reported more commonly in the high dose group:

Table 1: Dose-related Adverse Drug Reactions: ATLAS trial

Acute Myocardial Infarction

Patients in the GISSI-3 study, treated with Interpril, had a higher incidence of hypotension (9.0% vs 3.7%) and renal dysfunction (2.4% vs 1.1%) compared with patients not taking Interpril.

Other clinical adverse reactions occurring in 1% or higher of patients with hypertension or heart failure treated with Interpril in controlled clinical trials and do not appear in other sections of labeling are listed below:

Body as a whole: Fatigue, asthenia, orthostatic effects.

Digestive: Pancreatitis, constipation, flatulence, dry mouth, diarrhea.

Hematologic: Rare cases of bone marrow depression, hemolytic anemia, leukopenia/neutropenia and thrombocytopenia.

Endocrine: Diabetes mellitus, inappropriate antidiuretic hormone secretion.

Metabolic: Gout

Skin: Urticaria, alopecia, photosensitivity, erythema, flushing, diaphoresis, cutaneous pseudolymphoma, toxic epidermal necrolysis, Stevens. Johnson syndrome, and pruritus.

Special Senses: Visual loss, diplopia, blurred vision, tinnitus, photophobia, taste disturbances, olfactory disturbances.

Urogenital: Impotence

Miscellaneous: A symptom complex has been reported which may include a positive ANA, an elevated erythrocyte sedimentation rate, arthralgia/arthritis, myalgia, fever, vasculitis, eosinophilia, leukocytosis, paresthesia and vertigo. Rash, photosensitivity or other dermatological manifestations may occur alone or in combination with these symptoms.

Clinical Laboratory Test Findings

Serum Potassium: In clinical trials hyperkalemia (serum potassium >5.7 mEq/L) occurred in 2.2% and 4.8% of Interpril-treated patients with hypertension and heart failure, respectively.

Creatinine, Blood Urea Nitrogen

Minor increases in blood urea nitrogen and serum creatinine, reversible upon discontinuation of therapy, were observed in about 2% of patients with hypertension treated with Interpril alone. Increases were more common in patients receiving concomitant diuretics and in patients with renal artery stenosis. Reversible minor increases in blood urea nitrogen and serum creatinine were observed in 11.6% of patients with heart failure on concomitant diuretic therapy. Frequently, these abnormalities resolved when the dosage of the diuretic was decreased.

Patients with acute myocardial infarction in the GISSI-3 trial treated with Interpril had a higher (2.4% versus 1.1% in placebo) incidence of renal dysfunction in-hospital and at 6 weeks (increasing creatinine concentration to over 3 mg/dL or a doubling or more of the baseline serum creatinine concentration).

Hemoglobin and Hematocrit

Small decreases in hemoglobin (mean 0.4 mg/dL) and hematocrit (mean 1.3%) occurred frequently in patients treated with Interpril but were rarely of clinical importance in patients without some other cause of anemia. In clinical trials, fewer than 0.1% of patients discontinued therapy for anemia.

Liver Enzymes Rarely, elevations of liver enzymes and/or serum bilirubin have occurred.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of lisinopril that are not included in other sections of labeling. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Other reactions include:

Metabolism And Nutrition Disorders

Hyponatremia , cases of hypoglycemia in diabetic patients on oral antidiabetic agents or insulin

Nervous System And Psychiatric Disorders

Mood alterations (including depressive symptoms), mental confusion

Following a single oral dose of 20 g/kg no lethality occurred in rats, and death occurred in one of 20 mice receiving the same dose. The most likely manifestation of overdosage would be hypotension, for which the usual treatment would be intravenous infusion of normal saline solution.

Lisinopril can be removed by hemodialysis.

Following a single oral dose of 20 g/kg, no lethality occurred in rats and death occurred in one of 20 mice receiving the same dose. The most likely manifestation of overdosage would be hypotension, for which the usual treatment would be intravenous infusion of normal saline solution.

Lisinopril can be removed by hemodialysis.

Hypertension

Adult Patients

Administration of lisinopril to patients with hypertension results in a reduction of both supine and standing blood pressure to about the same extent with no compensatory tachycardia. Symptomatic postural hypotension is usually not observed although it can occur and should be anticipated in volume and/or salt-depleted patients. When given together with thiazide-type diuretics, the blood pressure lowering effects of the two drugs are approximately additive.

In most patients studied, onset of antihypertensive activity was seen at one hour after oral administration of an individual dose of lisinopril, with peak reduction of blood pressure achieved by 6 hours. Although an antihypertensive effect was observed 24 hours after dosing with recommended single daily doses, the effect was more consistent and the mean effect was considerably larger in some studies with doses of 20 mg or more than with lower doses; however, at all doses studied, the mean antihypertensive effect was substantially smaller 24 hours after dosing than it was 6 hours after dosing.

The antihypertensive effects of lisinopril are maintained during long-term therapy. Abrupt withdrawal of lisinopril has not been associated with a rapid increase in blood pressure, or a significant increase in blood pressure compared to pretreatment levels.

Non-Steroidal Anti-Inflammatory Agents

In a study in 36 patients with mild to moderate hypertension where the antihypertensive effects of lisinopril alone were compared lisinopril given concomitantly with indomethacin, the use of indomethacin was associated with a reduced effect, although the difference between the two regimens was not significant.

Hypertension

Adult Patients

Administration of Interpril to patients with hypertension results in a reduction of supine and standing blood pressure to about the same extent with no compensatory tachycardia. Symptomatic postural hypotension is usually not observed although it can occur and should be anticipated in volume and/or salt-depleted patients. When given together with thiazidetype diuretics, the blood pressure lowering effects of the two drugs are approximately additive.

In most patients studied, onset of antihypertensive activity was seen at one hour after oral administration of an individual dose of Interpril, with peak reduction of blood pressure achieved by 6 hours. Although an antihypertensive effect was observed 24 hours after dosing with recommended single daily doses, the effect was more consistent and the mean effect was considerably larger in some studies with doses of 20 mg or more than with lower doses. However, at all doses studied, the mean antihypertensive effect was substantially smaller 24 hours after dosing than it was 6 hours after dosing.

The antihypertensive effects of Interpril are maintained during long-term therapy. Abrupt withdrawal of Interpril has not been associated with a rapid increase in blood pressure or a significant increase in blood pressure compared to pretreatment levels.

Adult Patients

Interpril is bioequivalent to lisinopril tablets under fasted and fed conditions.

Following oral administration of lisinopril tablets, peak serum concentrations of lisinopril occur within about 7 hours, although there was a trend to a small delay in time taken to reach peak serum concentrations in acute myocardial infarction patients. Food does not alter the bioavailability of lisinopril tablets. Declining serum concentrations exhibit a prolonged terminal phase, which does not contribute to drug accumulation. This terminal phase probably represents saturable binding to ACE and is not proportional to dose. Upon multiple dosing, lisinopril exhibits an effective half-life of 12 hours.

Lisinopril does not appear to be bound to other serum proteins. Lisinopril does not undergo metabolism and is excreted unchanged entirely in the urine. Based on urinary recovery, the mean extent of absorption of lisinopril is approximately 25%, with large intersubject variability (6-60%) at all doses tested (5-80 mg). The absolute bioavailability of lisinopril is reduced to 16% in patients with stable NYHA Class II-IV congestive heart failure, and the volume of distribution appears to be slightly smaller than that in normal subjects. The oral bioavailability of lisinopril in patients with acute myocardial infarction is similar to that in healthy volunteers.

Impaired renal function decreases elimination of lisinopril, which is excreted principally through the kidneys, but this decrease becomes clinically important only when the glomerular filtration rate is below 30 mL/min. Above this glomerular filtration rate, the elimination half-life is little changed. With greater impairment, however, peak and trough lisinopril levels increase, time to peak concentration increases and time to attain steady state is prolonged. Lisinopril can be removed by hemodialysis.

Pediatric Patients

The pharmacokinetics of lisinopril were studied in 29 pediatric hypertensive patients between 6 years and 16 years with glomerular filtration rate > 30 mL/min/1.73 m². After doses of 0.1 to 0.2 mg per kg, steady state peak plasma concentrations of lisinopril occurred within 6 hours and the extent of absorption based on urinary recovery was about 28%. These values are similar to those obtained previously in adults. The typical value of lisinopril oral clearance (systemic clearance/absolute bioavailability) in a child weighing 30 kg is 10 L/h, which increases in proportion to renal function.

Adult Patients

Following oral administration of Interpril, peak serum concentrations of lisinopril occur within about 7 hours, although there was a trend to a small delay in time taken to reach peak serum concentrations in acute myocardial infarction patients. Declining serum concentrations exhibit a prolonged terminal phase which does not contribute to drug accumulation. This terminal phase probably represents saturable binding to ACE and is not proportional to dose. Upon multiple dosing, lisinopril exhibits an effective half-life of 12 hours.

Lisinopril does not appear to be bound to other serum proteins. Lisinopril does not undergo metabolism and is excreted unchanged entirely in the urine. Based on urinary recovery, the mean extent of absorption of lisinopril is approximately 25 percent, with large inter-subject variability (6-60 percent) at all doses tested (5-80 mg). Lisinopril absorption is not influenced by the presence of food in the gastrointestinal tract. The absolute bioavailability of lisinopril is reduced to about 16 percent in patients with stable NYHA Class II-IV congestive heart failure, and the volume of distribution appears to be slightly smaller than that in normal subjects.

The oral bioavailability of lisinopril in patients with acute myocardial infarction is similar to that in healthy volunteers.

Impaired renal function decreases elimination of lisinopril, which is excreted principally through the kidneys, but this decrease becomes clinically important only when the glomerular filtration rate is below 30 mL/min. Above this glomerular filtration rate, the elimination half-life is little changed. With greater impairment, however, peak and trough lisinopril levels increase, time to peak concentration increases and time to attain steady state is prolonged. Older patients, on average, have (approximately doubled) higher blood levels and area under the plasma concentration time curve (AUC) than younger patients. Lisinopril can be removed by hemodialysis.

Studies in rats indicate that lisinopril crosses the blood-brain barrier poorly. Multiple doses of lisinopril in rats do not result in accumulation in any tissues. Milk of lactating rats contains radioactivity following administration of ¹⁴C lisinopril. By whole body autoradiography, radioactivity was found in the placenta following administration of labeled drug to pregnant rats, but none was found in the fetuses.

Pediatric Patients

The pharmacokinetics of lisinopril were studied in 29 pediatric hypertensive patients between 6 years and 16 years with glomerular filtration rate >30 mL/min/1.73 m². After doses of 0.1 to 0.2 mg/kg, steady state peak plasma concentrations of lisinopril occurred within 6 hours and the extent of absorption based on urinary recovery was about 28%. These values are similar to those obtained previously in adults. The typical value of lisinopril oral clearance (systemic clearance/absolute bioavailability) in a child weighing 30 kg is 10 L/h, which increases in proportion to renal function.