IRBESARTAN: 10,144 Adverse Event Reports & Safety Profile

Irbesartan USP is an angiotensin II receptor (AT 1 subtype) antagonist. Irbesartan USP is a non-peptide compound, chemically described as a 2-butyl-3-[ p -( o -1 H -tetrazol-5-ylphenyl)benzyl]-1,3-diazaspiro[4.4]non-1-en-4-one. Its molecular formula is C 25 H 28 N 6 O, and the structural formula: Irbesartan USP is a white to off-white crystalline powder with a molecular weight of 428.5. It is a nonpolar compound with a partition coefficient (octanol/water) of 10.1 at pH of 7.4. Irbesartan USP is slightly soluble in alcohol and methylene chloride and practically insoluble in water. Irbesartan is available for oral administration in unscored film-coated tablets containing 75 mg, 150 mg, or 300 mg of irbesartan USP. Inactive ingredients include: carboxymethylcellulose calcium, povidone, colloidal silicon dioxide, sodium starch glycolate, talc and magnesium stearate. The film coating comprises of hypromellose, lactose monohydrate, titanium dioxide and polyethylene glycol. irbesartan

AND USAGE

1.1 Hypertension Irbesartan tablets, USP are indicated for the treatment of hypertension, to lower blood pressure. Lowering blood pressure lowers the risk of fatal and non-fatal cardiovascular (CV) events, primarily strokes and myocardial infarction. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes including this drug. 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. Irbesartan tablets, USP may be used alone or in combination with other antihypertensive agents.

1.2 Nephropathy in Type 2 Diabetic Patients Irbesartan tablets, USP are indicated for the treatment of diabetic nephropathy in patients with type 2 diabetes and hypertension, an elevated serum creatinine, and proteinuria (&gt;300 mg/day). In this population, irbesartan tablets, USP reduce the rate of progression of nephropathy as measured by the occurrence of doubling of serum creatinine or end-stage renal disease (need for dialysis or renal transplantation) <span class="opacity-50 text-xs">[see Clinical Studies ( 14.2 )]</span> . Irbesartan tablets, USP are, an angiotensin II receptor blocker (ARB) indicated for: Treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. ( 1.1 ) ​ Treatment of diabetic nephropathy in hypertensive patients with type 2 diabetes, an elevated serum creatinine, and proteinuria. ( 1.2 )

DOSAGE & ADMINISTRATION

2.1 General Considerations Irbesartan tablets may be administered with other antihypertensive agents and with or without food.

2.2 Hypertension The recommended initial dose of irbesartan tablets is 150 mg once daily. The dosage can be increased to a maximum dose of 300 mg once daily as needed to control blood pressure <span class="opacity-50 text-xs">[see Clinical Studies (14.1)]</span>.

2.3 Nephropathy in Type 2 Diabetic Patients The recommended dose is 300 mg once daily <span class="opacity-50 text-xs">[see Clinical Studies (14.2)]</span>.

2.4 Dose Adjustment in Volume- and Salt-Depleted Patients The recommended initial dose is 75 mg once daily in patients with depletion of intravascular volume or salt (e.g., patients treated vigorously with diuretics or on hemodialysis) <span class="opacity-50 text-xs">[see Warnings and Precautions (5.2)]</span>.

Dosage

Forms and Strengths Irbesartan Tablets USP, 75 mg are white to off white, capsule shaped, biconvex tablets debossed with '158' on one side and 'H' on the other side.

Irbesartan

Tablets USP, 150 mg are white to off white, capsule shaped, biconvex tablets debossed with '159' on one side and 'H' on the other side.

Irbesartan

Tablets USP, 300 mg are white to off white, capsule shaped, biconvex tablets debossed with '160' on one side and 'H' on the other side.

Irbesartan is contraindicated in patients who are hypersensitive to any component of this product. Do not coadministrate aliskiren with irbesartan in patients with diabetes. Irbesartan is contraindicated in patients who are hypersensitive to any component of this product. Do not coadministrate aliskiren with irbesartan in patients with diabetes.

REACTIONS The following important adverse reactions are described elsewhere in the labeling:

• Hypotension in Volume or Salt-Depleted Patients [see Warnings and Precautions ( 5.2 )]
• Impaired Renal Function [see Warnings and Precautions ( 5.3 )]
• Nephropathy in type 2 diabetic patients: The most common adverse reactions which were more frequent than placebo were hyperkalemia dizziness, orthostatic dizziness, and orthostatic hypotension. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Macleods Pharma USA, Inc. at 1-888-943-3210 or 1-855-926-3384 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The adverse reaction information from clinical trials does, however, provide a basis for identifying the adverse events that appear to be related to drug use and for approximating rates.

Hypertension

Irbesartan tablets has been evaluated for safety in more than 4300 patients with hypertension and about 5000 subjects overall. This experience includes 1303 patients treated for over 6 months and 407 patients for 1 year or more. In placebo-controlled clinical trials, the following adverse reactions were reported in at least 1% of patients treated with irbesartan tablets (n=1965) and at a higher incidence versus placebo (n=641), excluding those too general to be informative and those not reasonably associated with the use of drug because they were associated with the condition being treated or are very common in the treated population, include: diarrhea (3% vs 2%), dyspepsia/heartburn (2% vs 1%), and fatigue (4% vs 3%). Irbesartan use was not associated with an increased incidence of dry cough, as is typically associated with ACE inhibitor use. In placebo-controlled studies, the incidence of cough in irbesartan-treated patients was 2.8% versus 2.7% in patients receiving placebo. Nephropathy in Type 2 Diabetic Patients Hyperkalemia: In the Irbesartan Diabetic Nephropathy Trial (IDNT) (proteinuria ≥900 mg/day, and serum creatinine ranging from 1.0-3.0 mg/dL), the percent of patients with potassium >6 mEq/L was 18.6% in the irbesartan tablets group versus 6.0% in the placebo group. Discontinuations due to hyperkalemia in the irbesartan tablets group were 2.1% versus 0.4% in the placebo group. In IDNT, the adverse reactions were similar to those seen in patients with hypertension with the exception of an increased incidence of orthostatic symptoms which occurred more frequently in the irbesartan tablets versus placebo group: dizziness (10.2% vs 6.0%), orthostatic dizziness (5.4% vs 2.7%) and orthostatic hypotension (5.4% vs 3.2%).

6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of irbesartan tablets. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate reliably their frequency or to establish a causal relationship to drug exposure. Blood and lymphatic system : Anemia, Thrombocytopenia Ear and labyrinth : Tinnitus Gastrointestinal : Intestinal angioedema Hepatobiliary : Hepatitis, Jaundice Immune system : Anaphylactic reaction including anaphylactic shock Investigations : Increased liver function tests, Increased CPK (Creatine Phosphokinase) Metabolism and nutrition : Hyperkalemia, Hypoglycemia in diabetic patients Skin and subcutaneous tissue : Urticaria, Angioedema (involving swelling of the face, lips, pharynx, and/or tongue)

AND PRECAUTIONS

• Hypotension: Correct volume or salt depletion prior to administration. ( 5.2 )
• Monitor renal function and serum potassium. ( 5.3 )

5.1 Fetal Toxicity Irbesartan tablets 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. 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 irbesartan tablets as soon as possible <span class="opacity-50 text-xs">[see Use in Specific Populations ( 8.1 )]</span>.

5.2 Hypotension in Volume or Salt-Depleted Patients In patients with an activated renin-angiotensin system, such as volume or salt-depleted patients (e.g., those being treated with high doses of diuretics), symptomatic hypotension may occur after initialization of treatment with irbesartan tablets. Correct volume or salt depletion prior to administration of irbesartan tablets or use a lower starting dose <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.4 )]</span>.

5.3 Impaired Renal Function 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 heart failure, or volume depletion) may be at particular risk of developing acute renal failure or death on irbesartan tablets. Monitor renal function periodically in these patients. Consider withholding or discontinuing therapy in patients who develop a clinically significant decrease in renal function on irbesartan tablets <span class="opacity-50 text-xs">[see Drug Interactions ( 7.3 )]</span>.

PRECAUTIONS Impaired Renal Function As a consequence of inhibiting the renin-angiotensin-aldosterone system, changes in renal function may be anticipated in susceptible individuals. In patients whose renal function may depend on the activity of the renin-angiotensin-aldosterone system (eg, patients with severe congestive heart failure), treatment with angiotensin-converting-enzyme inhibitors has been associated with oliguria and/or progressive azotemia and (rarely) with acute renal failure and/or death. Irbesartan would be expected to behave similarly. In studies of ACE inhibitors in patients with unilateral or bilateral renal artery stenosis, increases in serum creatinine or BUN have been reported. There has been no known use of irbesartan in patients with unilateral or bilateral renal artery stenosis, but a similar effect should be anticipated. Information for Patients Pregnancy Female patients of childbearing age should be told about the consequences of exposure to irbesartan during pregnancy. Discuss treatment options with women planning to become pregnant. Patients should be asked to report pregnancies to their physicians as soon as possible.

Drug Interactions

Lithium: Increases in serum lithium concentrations and lithium toxicity have been reported with concomitant use of irbesartan or thiazide diuretics. Monitor lithium levels in patients receiving irbesartan and lithium. In vitro studies show significant inhibition of the formation of oxidized irbesartan metabolites with the known cytochrome CYP 2C9 substrates/inhibitors sulphenazole, tolbutamide and nifedipine. However, in clinical studies the consequences of concomitant irbesartan on the pharmacodynamics of warfarin were negligible. Based on in vitro data, no interaction would be expected with drugs whose metabolism is dependent upon cytochrome P450 isoenzymes 1A1, 1A2, 2A6, 2B6, 2D6, 2E1, or 3A4. In separate studies of patients receiving maintenance doses of warfarin, hydrochlorothiazide, or digoxin, irbesartan administration for 7 days had no effect on the pharmacodynamics of warfarin (prothrombin time) or pharmacokinetics of digoxin. The pharmacokinetics of irbesartan were not affected by coadministration of nifedipine or hydrochlorothiazide. Concomitant use of potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium may lead to increases in serum potassium.

7.1 Agents Increas ing Serum Potassium Coadministration of irbesartan with other drugs that raise serum potassium levels may result in hyperkalemia, sometimes severe. Monitor serum potassium in such patients.

7.2 Lithium Increases in serum lithium concentrations and lithium toxicity have been reported with concomitant use of irbesartan and lithium. Monitor lithium levels in patients receiving irbesartan and lithium.

7.3 Non-Steroidal Anti-Inflammatory Drugs (NSAIDs )

Including Selective

Cyclooxygenas e-2 Inhibitors (COX-2 Inhibitors ) In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, co-administration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists (including irbesartan) may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving irbesartan and NSAID therapy. The antihypertensive effect of angiotensin II receptor antagonists, including irbesartan, may be attenuated by NSAIDs including selective COX-2 inhibitors.

7.4 Dual Blockade of the Renin-Angiotens in Sys tem (RAS) Dual blockade of the RAS with angiotensin receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy. Most patients receiving the combination of two RAS inhibitors do not obtain any additional benefit compared to monotherapy. In general, avoid combined use of RAS inhibitors. Closely monitor blood pressure, renal function and electrolytes in patients on irbesartan and other agents that affect the RAS. Do not co-administer aliskiren with irbesartan in patients with diabetes. Avoid use of aliskiren with irbesartan in patients with renal impairment (GFR &lt;60 mL/min). Non-Steroidal Anti-Inflammatory Agents Including Selective Cyclooxygenase-2 Inhibitors (COX-2 Inhibitors) In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, coadministration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists, including irbesartan, may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving irbesartan and NSAID therapy. The antihypertensive effect of angiotensin II receptor antagonists, including irbesartan, may be attenuated by NSAIDs including selective COX-2 inhibitors.

Dual

Blockade of the Renin-Angiotensin System (RAS) Dual blockade of the RAS with angiotensin-receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy. Closely monitor blood pressure, renal function, and electrolytes in patients on irbesartan and other agents that affect the RAS. In most patients no benefit has been associated with using two RAS inhibitors concomitantly. In general, avoid combined use of RAS inhibitors. Do not co-administer aliskiren with irbesartan in patients with diabetes. Avoid use of aliskiren with irbesartan in patients with renal impairment (GFR <60 mL/min). Carcinogenesis & Mutagenesis & Impairment Of Fertility No evidence of carcinogenicity was observed when irbesartan was administered at doses of up to 500/1000 mg/kg/day (males/females, respectively) in rats and 1000 mg/kg/day in mice for up to 2 years. For male and female rats, 500 mg/kg/day provided an average systemic exposure to irbesartan (AUC 0 to 24 hour , bound plus unbound) about 3 and 11 times, respectively, the average systemic exposure in humans receiving the maximum recommended dose (MRD) of 300 mg irbesartan/day, whereas 1000 mg/kg/day (administered to females only) provided an average systemic exposure about 21 times that reported for humans at the MRD. For male and female mice, 1000 mg/kg/day provided an exposure to irbesartan about 3 and 5 times, respectively, the human exposure at 300 mg/day. Irbesartan was not mutagenic in a battery of in vitro tests (Ames microbial test, rat hepatocyte DNA repair test, V79 mammalian-cell forward gene-mutation assay). Irbesartan was negative in several tests for induction of chromosomal aberrations ( in vitro -human lymphocyte assay; in vivo -mouse micronucleus study). Irbesartan had no adverse effects on fertility or mating of male or female rats at oral doses ≤650 mg/kg/day, the highest dose providing a systemic exposure to irbesartan (AUC 0 to 24 hour , bound plus unbound) about 5 times that found in humans receiving the maximum recommended dose of 300 mg/day.

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 irbesartan as soon as possible. These adverse outcomes are usually associated with use of these drugs in the second and third trimesters 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 to therapy with 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 irbesartan, 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 irbesartan for hypotension, oliguria, and hyperkalemia [see Use in Specific Populations (8.4)]. Irbesartan crosses the placenta in rats and rabbits. In pregnant rats given irbesartan at doses greater than the maximum recommended human dose (MRHD), fetuses showed increased incidences of renal pelvic cavitation, hydroureter and/or absence of renal papilla. Subcutaneous edema also occurred in fetuses at doses about 4 times the MRHD (based on body surface area). These anomalies occurred when pregnant rats received irbesartan through Day 20 of gestation but not when drug was stopped on gestation Day 15. The observed effects are believed to be late gestational effects of the drug. Pregnant rabbits given oral doses of irbesartan equivalent to 1.5 times the MRHD experienced a high rate of maternal mortality and abortion. Surviving females had a slight increase in early resorptions and a corresponding decrease in live fetuses [see Nonclinical Toxicology (13.2)]. Radioactivity was present in the rat and rabbit fetus during late gestation and in rat milk following oral doses of radiolabeled irbesartan.

Nursing

Mothers It is not known whether irbesartan is excreted in human milk, but irbesartan or some metabolite of irbesartan is secreted at low concentration in the milk of lactating rats. Because of the potential for adverse effects on the nursing infant, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric

Use In infants with histories of in utero exposure to an angiotensin II receptor antagonist observe for hypotension, oliguria, and hyperkalemia. If oliguria occurs, support blood pressure and renal perfusion. Exchange transfusion or dialysis may be required as means of reversing hypotension and/or substituting for disordered renal function. Irbesartan, in a study at a dose of up to 4.5 mg/kg/day, once daily, did not appear to lower blood pressure effectively in pediatric patients ages 6 to 16 years. Irbesartan has not been studied in pediatric patients less than 6 years old.

Geriatric Use Of

4925 subjects receiving irbesartan in controlled clinical studies of hypertension, 911 (18.5%) were 65 years and over, while 150 (3%) were 75 years and over. No overall differences in effectiveness or safety were observed between these subjects and younger subjects, but greater sensitivity of some older individuals cannot be ruled out. (See CLINICAL PHARMACOLOGY : Pharmacokinetics , Special Populations , and Clinical Studies . )

Drug Interactions Lithium: Increases in serum lithium concentrations and lithium toxicity have been reported with concomitant use of irbesartan or thiazide diuretics. Monitor lithium levels in patients receiving irbesartan and lithium. In vitro studies show significant inhibition of the formation of oxidized irbesartan metabolites with the known cytochrome CYP 2C9 substrates/inhibitors sulphenazole, tolbutamide and nifedipine. However, in clinical studies the consequences of concomitant irbesartan on the pharmacodynamics of warfarin were negligible. Based on in vitro data, no interaction would be expected with drugs whose metabolism is dependent upon cytochrome P450 isoenzymes 1A1, 1A2, 2A6, 2B6, 2D6, 2E1, or 3A4. In separate studies of patients receiving maintenance doses of warfarin, hydrochlorothiazide, or digoxin, irbesartan administration for 7 days had no effect on the pharmacodynamics of warfarin (prothrombin time) or pharmacokinetics of digoxin. The pharmacokinetics of irbesartan were not affected by coadministration of nifedipine or hydrochlorothiazide. Concomitant use of potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium may lead to increases in serum potassium.

7.1 Agents Increas ing Serum Potassium Coadministration of irbesartan with other drugs that raise serum potassium levels may result in hyperkalemia, sometimes severe. Monitor serum potassium in such patients.

7.2 Lithium Increases in serum lithium concentrations and lithium toxicity have been reported with concomitant use of irbesartan and lithium. Monitor lithium levels in patients receiving irbesartan and lithium.

7.3 Non-Steroidal Anti-Inflammatory Drugs (NSAIDs )

Including Selective

Cyclooxygenas e-2 Inhibitors (COX-2 Inhibitors ) In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, co-administration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists (including irbesartan) may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving irbesartan and NSAID therapy. The antihypertensive effect of angiotensin II receptor antagonists, including irbesartan, may be attenuated by NSAIDs including selective COX-2 inhibitors.

7.4 Dual Blockade of the Renin-Angiotens in Sys tem (RAS) Dual blockade of the RAS with angiotensin receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy. Most patients receiving the combination of two RAS inhibitors do not obtain any additional benefit compared to monotherapy. In general, avoid combined use of RAS inhibitors. Closely monitor blood pressure, renal function and electrolytes in patients on irbesartan and other agents that affect the RAS. Do not co-administer aliskiren with irbesartan in patients with diabetes. Avoid use of aliskiren with irbesartan in patients with renal impairment (GFR &lt;60 mL/min).

7.1 Agents Increas ing Serum Potassium Coadministration of irbesartan with other drugs that raise serum potassium levels may result in hyperkalemia, sometimes severe. Monitor serum potassium in such patients.

7.2 Lithium Increases in serum lithium concentrations and lithium toxicity have been reported with concomitant use of irbesartan and lithium. Monitor lithium levels in patients receiving irbesartan and lithium.

7.3 Non-Steroidal Anti-Inflammatory Drugs (NSAIDs )

Including Selective

Cyclooxygenas e-2 Inhibitors (COX-2 Inhibitors ) In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, co-administration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists (including irbesartan) may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving irbesartan and NSAID therapy. The antihypertensive effect of angiotensin II receptor antagonists, including irbesartan, may be attenuated by NSAIDs including selective COX-2 inhibitors.

7.4 Dual Blockade of the Renin-Angiotens in Sys tem (RAS) Dual blockade of the RAS with angiotensin receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy. Most patients receiving the combination of two RAS inhibitors do not obtain any additional benefit compared to monotherapy. In general, avoid combined use of RAS inhibitors. Closely monitor blood pressure, renal function and electrolytes in patients on irbesartan and other agents that affect the RAS. Do not co-administer aliskiren with irbesartan in patients with diabetes. Avoid use of aliskiren with irbesartan in patients with renal impairment (GFR &lt;60 mL/min).