Irbesartan Prescribing Information
5.1 Fetal ToxicityIrbesartan 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 as soon as possible
8.1 PregnancyIrbesartan 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
All pregnancies have a background risk of birth defect, loss or other adverse outcomes regardless of drug exposure. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Disease-associated maternal and/or embryo-fetal risk
Hypertension in pregnancy increases the maternal risk for preeclampsia, gestational diabetes, premature delivery, and delivery complications (e.g., need for cesarean section and postpartum 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, skeletal deformations, including skull hypoplasia, hypotension, and death.
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. 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. If oligohydramnios is observed, consider alternative treatment. Closely observe infants with histories of in utero exposure to irbesartan for hypotension, oliguria, and hyperkalemia and other symptoms of renal impairment. In neonates with a history of in utero exposure to irbesartan, if oliguria or hypotension occurs, direct attention toward support of blood pressure and renal perfusion. Exchange transfusion or dialysis may be required as means of reversing hypotension and/or substituting for disordered renal function.
Animal data
Irbesartan crosses the placenta in rats and rabbits. In female rats given irbesartan prior to mating through gestation and lactation at oral doses of 50, 180, or 650 mg/kg/day (1.6 to 21.1 times the maximum recommended human dose (MRHD) based on body surface area), fetuses examined on Gestation Day 20 showed increased incidences of hydroureter and renal pelvic cavitation and/or absence of renal papilla in all irbesartan-treated groups. Subcutaneous edema also occurred in fetuses at maternal doses ≥180 mg/kg/day (5.8 times the MRHD). These anomalies occurred when female rats received irbesartan from prior to mating through Day 20 of gestation but were not observed in pups postnatally in the same study, or when irbesartan was given to pregnant rats only during organogenesis (Gestation Day 6 through Gestation Day 15) at oral doses from 50 to 450 mg/kg/day (up to 14.6 times the MRHD). In addition, no adverse effects on kidney development were observed in pups from dams given irbesartan from Gestation Day 15 through Lactation Day 24 at doses of 50, 180, or 650 mg/kg/day (up to 21.1 times the MRHD). The observed effects are believed to be late gestational effects of the drug. Pregnant rabbits given oral doses of irbesartan of 30 mg/kg/day (1.9 times the MRHD based on body surface area) 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.
Radioactivity was present in the rat and rabbit fetuses during late gestation following oral doses of radiolabeled irbesartan.
• Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus
5.1 Fetal ToxicityIrbesartan 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 as soon as possible
Indication | Dose |
Hypertension2.2 HypertensionThe 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 [see Clinical Studies (14.1)]. | 150 to 300 mg once daily |
Diabetic Nephropathy2.3 Nephropathy in Type 2 Diabetic PatientsThe recommended dose is 300 mg once daily [see Clinical Studies (14.2)] . | 300 mg once daily |
Irbesartan tablets, USP 75 mg are available as white to off-white, biconvex, oval shaped tablets, debossed with ‘447’ on one side and ‘C’ on the other.
Irbesartan tablets, USP 150 mg are available as white to off-white, biconvex, oval shaped tablets, debossed with ‘448’ on one side and ‘C’ on the other.
Irbesartan tablets, USP 300 mg are available as white to off-white, biconvex, oval shaped tablets, debossed with ‘449’ on one side and ‘C’ on the other.
Irbesartan is contraindicated in patients who are hypersensitive to any component of this product.
Do not coadministrate aliskiren with irbesartan in patients with diabetes.
- Hypotension: Correct volume or salt depletion prior to administration.
5.2 Hypotension in Volume or Salt-Depleted PatientsIn 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. Correct volume or salt depletion prior to administration of irbesartan or use a lower starting dose
[see Dosage and Administration (2.4)]. - Monitor renal function and serum potassium.
5.3 Impaired Renal FunctionChanges 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. 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
[see Drug Interactions (7.3)].
The following important adverse reactions are described elsewhere in the labeling:
- Hypotension in Volume or Salt-Depleted Patients [see]
5.2 Hypotension in Volume or Salt-Depleted PatientsIn 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. Correct volume or salt depletion prior to administration of irbesartan or use a lower starting dose
[see Dosage and Administration (2.4)]. - Impaired Renal Function [see]
5.3 Impaired Renal FunctionChanges 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. 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
[see Drug Interactions (7.3)].