amlodipine 5 MG Powder for Oral Solution

INDICATIONS AND USAGE Amlodipine besylate is a calcium channel blocker and may be used alone or in combination with other antihypertensive and antianginal agents for the treatment of: Hypertension ( 1.1 ) Amlodipine besylate tablet, USP is 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 Coronary Artery Disease ( 1.2 ) Chronic Stable Angina Vasospastic Angina (Prinzmetal's or Variant Angina) Angiographically Documented Coronary Artery Disease in patients without heart failure or an ejection fraction < 40% 1.1 Hypertension Amlodipine besylate tablet, USP is 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 including amlodipine besylate tablet, USP. 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. Amlodipine besylate tablet, USP may be used alone or in combination with other antihypertensive agents. 1.2 Coronary Artery Disease (CAD) Chronic Stable Angina Amlodipine besylate tablet, USP is indicated for the symptomatic treatment of chronic stable angina. Amlodipine besylate tablet, USP may be used alone or in combination with other antianginal agents. Vasospastic Angina (Prinzmetal’s or Variant Angina) Amlodipine besylate tablet, USP is indicated for the treatment of confirmed or suspected vasospastic angina. Amlodipine besylate tablet, USP may be used as monotherapy or in combination with other antianginal agents. Angiographically Documented CAD In patients with recently documented CAD by angiography and without heart failure or an ejection fraction <40%, Amlodipine besylate tablet, USP is indicated to reduce the risk of hospitalization for angina and to reduce the risk of a coronary revascularization procedure. 1.1 Hypertension Amlodipine besylate tablet, USP is 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 including amlodipine besylate tablet, USP. 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. Amlodipine besylate tablet, USP may be used alone or in combination with other antihypertensive agents. 1.2 Coronary Artery Disease (CAD) Chronic Stable Angina Amlodipine besylate tablet, USP is indicated for the symptomatic treatment of chronic stable angina. Amlodipine besylate tablet, USP may be used alone or in combination with other antianginal agents. Vasospastic Angina (Prinzmetal’s or Variant Angina) Amlodipine besylate tablet, USP is indicated for the treatment of confirmed or suspected vasospastic angina. Amlodipine besylate tablet, USP may be used as monotherapy or in combination with other antianginal agents. Angiographically Documented CAD In patients with recently documented CAD by angiography and without heart failure or an ejection fraction <40%, Amlodipine besylate tablet, USP is indicated to reduce the risk of hospitalization for angina and to reduce the risk of a coronary revascularization procedure.

DOSAGE AND ADMINISTRATION Amlodipine and Atorvastatin Tablets Dosage of amlodipine and atorvastatin tablets must be individualized on the basis of both effectiveness and tolerance for each individual component in the treatment of hypertension/angina and hyperlipidemia. Select doses of amlodipine and atorvastatin independently. Amlodipine and atorvastatin tablets may be substituted for its individually titrated components. Patients may be given the equivalent dose of amlodipine and atorvastatin tablets or a dose of amlodipine and atorvastatin tablets with increased amounts of amlodipine, atorvastatin, or both for additional antianginal effects, blood pressure lowering, or lipid-lowering effect. Amlodipine and atorvastatin tablets may be used to provide additional therapy for patients already on one of its components. Amlodipine and atorvastatin tablets may be used to initiate treatment in patients with hyperlipidemia and either hypertension or angina. Important Dosage Information Take amlodipine and atorvastatin tablets orally once daily at any time of the day, with or without food. Amlodipine The usual initial antihypertensive oral dosage of amlodipine is 5 mg once daily, and the maximum dose is 10 mg once daily. Pediatric (age > 6 years), small adult, fragile, or elderly patients, or patients with hepatic insufficiency may be started on 2.5 mg once daily and this dose may be used when adding amlodipine to other antihypertensive therapy. Adjust dosage according to blood pressure goals. In general, wait 7 to 14 days between titration steps. Titration may proceed more rapidly, however, if clinically warranted, provided the patient is assessed frequently. Angina The recommended dosage of amlodipine for chronic stable or vasospastic angina is 5 to 10 mg, with the lower dose suggested in the elderly and in patients with hepatic insufficiency. Most patients will require 10 mg for adequate effect. Coronary Artery Disease The recommended dosage range of amlodipine for patients with CAD is 5 to 10 mg once daily. In clinical studies, the majority of patients required 10 mg [see Clinical Studies (14.4)] . Pediatrics The effective antihypertensive oral dose of amlodipine in pediatric patients ages 6 to 17 years is 2.5 mg to 5 mg once daily. Doses in excess of 5 mg daily have not been studied in pediatric patients [see Clinical Pharmacology (12.3) and Clinical Studies (14.1)] . Atorvastatin Assess LDL-C when clinically appropriate, as early as 4 weeks after initiating atorvastatin, and adjust the dosage if necessary. Recommended Dosage in Adult Patients The recommended starting dosage of atorvastatin is 10 mg to 20 mg once daily. The dosage range is 10 mg to 80 mg once daily. Patients who require reduction in LDL-C greater than 45% may be started at 40 mg once daily. Recommended Dosage in Pediatric Patients 10 Years of Age and Older with HeFH The recommended starting dosage of atorvastatin is 10 mg once daily. The dosage range is 10 mg to 20 mg once daily. Recommended Dosage in Pediatric Patients 10 Years of Age and Older with HoFH The recommended starting dosage of atorvastatin is 10 mg to 20 mg once daily. The dosage range is 10 mg to 80 mg once daily. Dosage Modifications Due to Drug Interactions Concomitant use of atorvastatin with the following drugs requires dosage modification of atorvastatin [see Warnings and Precautions (5.1) and Drug Interactions (7.1)]. Anti-Viral Medications • In patients taking saquinavir plus ritonavir, darunavir plus ritonavir, fosamprenavir, fosamprenavir plus ritonavir, elbasvir plus grazoprevir or letermovir, do not exceed atorvastatin 20 mg once daily. • In patients taking nelfinavir, do not exceed atorvastatin 40 mg once daily. Select Azole Antifungals or Macrolide Antibiotics • In patients taking clarithromycin or itraconazole, do not exceed atorvastatin 20 mg once daily. For additional recommendations regarding concomitant use of atorvastatin with other anti-viral medications, azole antifungals or macrolide antibiotics, [see Drug Interactions (7.1)] . Usual Starting Dose (mg daily) Maximum Dose (mg daily) Amlodipine 5 a 10 Atorvastatin 10 to 20 b 80 a Start small adults or children, fragile, or elderly patients, or patients with hepatic insufficiency on 2.5 mg once daily ( 2 ). b Start patients requiring large LDL-C reduction (> 45%) at 40 mg once daily ( 2 ).

WARNINGS AND PRECAUTIONS • Anaphylactoid reactions, including angioedema. (5.1) • Myocardial infarction or increased angina in patients with obstructive coronary artery disease. (5.2) • Assess for hypotension and hyperkalemia. ( 5.4 , 5.8 ) • Titrate slowly in patients with impaired hepatic or severely impaired renal function. ( 5.6 , 5.7 ) 5.1 Anaphylactoid and Possibly Related Reactions Presumably because angiotensin-converting enzyme inhibitors affect the metabolism of eicosanoids and polypeptides, including endogenous bradykinin, patients receiving ACE inhibitors (including amlodipine and benazepril hydrochloride) may be subject to a variety of adverse reactions, some of them serious. These reactions usually occur after one of the first few doses of the ACE inhibitor, but they sometimes do not appear until after months of therapy. Black patients receiving ACE inhibitors have a higher incidence of angioedema compared to nonblacks. Patients receiving coadministration of 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 [see Drug Interactions (7) ] . Head and Neck Angioedema: Angioedema of the face, extremities, lips, tongue, glottis, and larynx has been reported in patients treated with ACE inhibitors. In U.S. clinical trials, symptoms consistent with angioedema were seen in none of the subjects who received placebo and in about 0.5% of the subjects who received benazepril. Angioedema associated with laryngeal edema can be fatal. If laryngeal stridor or angioedema of the face, tongue, or glottis occurs, discontinue treatment with amlodipine and benazepril hydrochloride and treat immediately. When involvement of the tongue, glottis, or larynx appears likely to cause airway obstruction, appropriate therapy, e.g., administer subcutaneous epinephrine injection 1:1000 (0.3 to 0.5 mL), promptly [see Adverse Reactions (6) ] . Intestinal Angioedema: Intestinal angioedema has been reported 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. The angioedema was diagnosed by procedures including abdominal CT scan or ultrasound, or at surgery, and symptoms resolved after stopping the ACE inhibitor. Intestinal angioedema should be included in the differential diagnosis of patients on ACE inhibitors presenting with abdominal pain. Anaphylactoid Reactions During Desensitization: Two patients undergoing desensitizing treatment with hymenoptera (wasp sting) venom while receiving ACE inhibitors sustained life-threatening anaphylactoid reactions. In the same patients, these reactions were avoided when ACE inhibitors were temporarily withheld, but they reappeared upon inadvertent rechallenge. Anaphylactoid Reactions During Membrane Exposure: Anaphylactoid reactions have been reported in patients dialyzed with high-flux membranes and treated concomitantly with an ACE inhibitor. Anaphylactoid reactions have also been reported in patients undergoing low-density lipoprotein apheresis with dextran sulfate absorption. 5.2 Increased Angina and/or Myocardial Infarction Worsening angina and acute myocardial infarction can develop after starting or increasing the dose of amlodipine, particularly in patients with severe obstructive coronary artery disease. 5.3 Patients with Aortic and Mitral Valve Stenosis, Obstructive Hypertrophic Cardiomyopathy As with all other vasodilators, special caution is required when using amlodipine in patients suffering from aortic or mitral stenosis, or obstructive hypertrophic cardiomyopathy. 5.4 Hypotension Amlodipine and benazepril hydrochloride can cause symptomatic hypotension. Symptomatic hypotension is most likely to occur in patients who have been volume or salt depleted as a result of diuretic therapy, dietary salt restriction, dialysis, diarrhea, or vomiting. Volume and/or salt depletion should be corrected before starting therapy with benazepril. If hypotension occurs, the patient should be placed in the supine position and if necessary given physiological saline intravenously. Treatment with benazepril can be continued once blood pressure and volume have returned to normal. In patients with congestive heart failure, with or without associated renal insufficiency, ACE inhibitor therapy may cause excessive hypotension, which may be associated with oliguria, azotemia, and (rarely) with acute renal failure and death. In such patients, start amlodipine and benazepril hydrochloride therapy under close medical supervision; follow closely for the first 2 weeks of treatment and whenever the dose of the benazepril component is increased or a diuretic is added or its dose increased. Symptomatic hypotension is also possible in patients with severe aortic stenosis. 5.5 Fetal Toxicity Pregnancy Category D Use of drugs that act on the RAS 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 amlodipine and benazepril hydrochloride as soon as possible [see Use in Specific Populations (8.1)] . 5.6 Hepatitis and Hepatic Failure There have been rare reports of predominantly cholestatic hepatitis and isolated cases of acute liver failure, some of them fatal, in patients on ACE inhibitors. The mechanism is not understood. Patients receiving ACE inhibitors who develop jaundice or marked elevation of hepatic enzymes should discontinue the ACE inhibitor and be kept under medical surveillance. 5.7 Impaired Renal Function Monitor renal function periodically in patients treated with amlodipine and benazepril hydrochloride. Changes in renal function, including acute renal failure, can be caused by drugs that affect the RAS. Patients whose renal function may depend in part on the activity of the RAS (e.g., patients with renal artery stenosis, severe heart failure, post-myocardial infarction or volume depletion) or who are on NSAIDs or ARBs may be at particular risk of developing acute renal failure on amlodipine and benazepril hydrochloride. Consider withholding or discontinuing therapy in patients who develop a clinically significant decrease in renal function on amlodipine and benazepril hydrochloride. 5.8 Hyperkalemia Monitor serum potassium periodically in patients receiving amlodipine and benazepril hydrochloride. Drugs that affect the RAS 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. In U.S. placebo-controlled trials of amlodipine and benazepril hydrochloride, hyperkalemia [serum potassium at least 0.5 mEq/L greater than the upper limit of normal (ULN)] not present at baseline occurred in approximately 1.5% of hypertensive patients receiving amlodipine and benazepril hydrochloride. Increases in serum potassium were generally reversible. 5.9 Cough Presumably due to the inhibition of the degradation of endogenous bradykinin, persistent nonproductive cough has been reported with all ACE inhibitors, generally resolving after discontinuation of therapy. Consider ACE inhibitor-induced cough in the differential diagnosis of cough. 5.10 Surgery/Anesthesia In patients undergoing surgery or during anesthesia with agents that produce hypotension, benazepril will block the angiotensin II formation that could otherwise occur secondary to compensatory renin release. Hypotension that occurs as a result of this mechanism can be corrected by volume expansion. A

CONTRAINDICATIONS • Do not coadminister aliskiren with angiotensin receptor blockers (ARBs), ACE inhibitors, including amlodipine and benazepril hydrochloride capsules in patients with diabetes. • Amlodipine and benazepril hydrochloride capsules are contraindicated in patients with a history of angioedema, with or without previous ACE inhibitor treatment, or patients who are hypersensitive to benazepril, to any other ACE inhibitor, to amlodipine, or to any of the excipients of amlodipine and benazepril hydrochloride capsules. • Amlodipine and benazepril hydrochloride capsules are contraindicated in combination with a neprilysin inhibitor (e.g., sacubitril). Do not administer amlodipine and benazepril hydrochloride capsules within 36 hours of switching to or from a neprilysin inhibitor, e.g., sacubitril/valsartan (see Warnings and Precautions 5.1 ). • Do not coadminister aliskiren with ACE inhibitors, including amlodipine and benazepril hydrochloride capsules, in patients with diabetes. (4) • Amlodipine and benazepril hydrochloride capsules are contraindicated in patients with a history of angioedema or patients who are hypersensitive to benazepril or to amlodipine. (4) • Amlodipine and benazepril hydrochloride capsules are contraindicated in combination with a neprilysin inhibitor (e.g., sacubitril). Do not administer amlodipine and benazepril hydrochloride capsules within 36 hours of switching to or from a neprilysin inhibitor, e.g., sacubitril/valsartan (see Warnings and Precautions 5.1 ).

Mechanism of Action Amlodipine is a dihydropyridine calcium antagonist (calcium ion antagonist or slow-channel blocker) that inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle. Experimental data suggest that amlodipine binds to both dihydropyridine and nondihydropyridine binding sites. The contractile processes of cardiac muscle and vascular smooth muscle are dependent upon the movement of extracellular calcium ions into these cells through specific ion channels. Amlodipine inhibits calcium ion influx across cell membranes selectively, with a greater effect on vascular smooth muscle cells than on cardiac muscle cells. Negative inotropic effects can be detected in vitro but such effects have not been seen in intact animals at therapeutic doses. Serum calcium concentration is not affected by amlodipine. Within the physiologic pH range, amlodipine is an ionized compound (pKa=8.6), and its kinetic interaction with the calcium channel receptor is characterized by a gradual rate of association and dissociation with the receptor binding site, resulting in a gradual onset of effect. Amlodipine is a peripheral arterial vasodilator that acts directly on vascular smooth muscle to cause a reduction in peripheral vascular resistance and reduction in blood pressure. The precise mechanisms by which amlodipine relieves angina have not been fully delineated, but are thought to include the following: Exertional Angina: In patients with exertional angina, amlodipine reduces the total peripheral resistance (afterload) against which the heart works and reduces the rate pressure product, and thus myocardial oxygen demand, at any given level of exercise. Vasospastic Angina: Amlodipine has been demonstrated to block constriction and restore blood flow in coronary arteries and arterioles in response to calcium, potassium epinephrine, serotonin, and thromboxane A2 analog in experimental animal models and in human coronary vessels in vitro. This inhibition of coronary spasm is responsible for the effectiveness of amlodipine in vasospastic (Prinzmetal's or variant) angina. 12.2 Pharmacodynamics Hemodynamics: Following administration of therapeutic doses to patients with hypertension, amlodipine produces vasodilation resulting in a reduction of supine and standing blood pressures. These decreases in blood pressure are not accompanied by a significant change in heart rate or plasma catecholamine levels with chronic dosing. Although the acute intravenous administration of amlodipine decreases arterial blood pressure and increases heart rate in hemodynamic studies of patients with chronic stable angina, chronic oral administration of amlodipine in clinical trials did not lead to clinically significant changes in heart rate or blood pressures in normotensive patients with angina. With chronic once daily oral administration, antihypertensive effectiveness is maintained for at least 24 hours. Plasma concentrations correlate with effect in both young and elderly patients. The magnitude of reduction in blood pressure with amlodipine is also correlated with the height of pretreatment elevation; thus, individuals with moderate hypertension (diastolic pressure 105–114 mmHg) had about a 50% greater response than patients with mild hypertension (diastolic pressure 90–104 mmHg). Normotensive subjects experienced no clinically significant change in blood pressures (+1/–2 mmHg). In hypertensive patients with normal renal function, therapeutic doses of amlodipine resulted in a decrease in renal vascular resistance and an increase in glomerular filtration rate and effective renal plasma flow without change in filtration fraction or proteinuria. As with other calcium channel blockers, hemodynamic measurements of cardiac function at rest and during exercise (or pacing) in patients with normal ventricular function treated with amlodipine have generally demonstrated a small increase in cardiac index without significant influence on dP/dt or on left ventricular end diastolic pressure or volume. In hemodynamic studies, amlodipine has not been associated with a negative inotropic effect when administered in the therapeutic dose range to intact animals and man, even when co-administered with beta-blockers to man. Similar findings, however, have been observed in normal or well-compensated patients with heart failure with agents possessing significant negative inotropic effects. Electrophysiologic Effects: Amlodipine does not change sinoatrial nodal function or atrioventricular conduction in intact animals or man. In patients with chronic stable angina, intravenous administration of 10 mg did not significantly alter A-H and H-V conduction and sinus node recovery time after pacing. Similar results were obtained in patients receiving amlodipine and concomitant beta-blockers. In clinical studies in which amlodipine was administered in combination with beta-blockers to patients with either hypertension or angina, no adverse effects on electrocardiographic parameters were observed. In clinical trials with angina patients alone, Amlodipine therapy did not alter electrocardiographic intervals or produce higher degrees of AV blocks. Drug interactions Sildenafil: When amlodipine and sildenafil were used in combination, each agent independently exerted its own blood pressure lowering effect [see Drug Interactions (7.1)]. 12.3 Pharmacokinetics After oral administration of therapeutic doses of amlodipine, absorption produces peak plasma concentrations between 6 and 12 hours. Absolute bioavailability has been estimated to be between 64 and 90%. The bioavailability of amlodipine is not altered by the presence of food. Amlodipine is extensively (about 90%) converted to inactive metabolites via hepatic metabolism with 10% of the parent compound and 60% of the metabolites excreted in the urine. Ex vivo studies have shown that approximately 93% of the circulating drug is bound to plasma proteins in hypertensive patients. Elimination from the plasma is biphasic with a terminal elimination half-life of about 30–50 hours. Steady-state plasma levels of amlodipine are reached after 7 to 8 days of consecutive daily dosing. The pharmacokinetics of amlodipine are not significantly influenced by renal impairment. Patients with renal failure may therefore receive the usual initial dose. Elderly patients and patients with hepatic insufficiency have decreased clearance of amlodipine with a resulting increase in AUC of approximately 40–60%, and a lower initial dose may be required. A similar increase in AUC was observed in patients with moderate to severe heart failure. Drug interactions In vitro data indicate that amlodipine has no effect on the human plasma protein binding of digoxin, phenytoin, warfarin, and indomethacin. Impact of other drugs on amlodipine Co-administered cimetidine, magnesium-and aluminum hydroxide antacids, sildenafil, and grapefruit juice have no impact on the exposure to amlodipine. CYP3A inhibitors: Co-administration of a 180 mg daily dose of diltiazem with 5 mg amlodipine in elderly hypertensive patients resulted in a 60% increase in amlodipine systemic exposure. Erythromycin co-administration in healthy volunteers did not significantly change amlodipine systemic exposure. However, strong inhibitors of CYP3A (e.g., itraconazole, clarithromycin) may increase the plasma concentrations of amlodipine to a greater extent [see Drug Interactions (7.1)]. Impact of amlodipine on other drugs Amlodipine is a weak inhibitor of CYP3A and may increase exposure to CYP3A substrates. Co-administered amlodipine does not affect the exposure to atorvastatin, digoxin, ethanol and the warfarin prothrombin response time. Simvastatin: Co-administration of multiple doses of 10 mg of amlodipine with 80 mg simvastatin resulted in a 77% increase in exposure to simvastatin compared to simvastatin alone [see Drug Interactions (7.2)]. Cyclosporine: A prospective study in renal transplant patie