Irbesartan Zentiva
Angiotensin II Receptor Blocker (ARB) for Hypertension and Diabetic Nephropathy
Quick Facts About Irbesartan Zentiva
Key Takeaways About Irbesartan Zentiva
- Effective blood pressure control: Irbesartan lowers blood pressure by blocking angiotensin II receptors, with full effect typically seen within 4–6 weeks of regular use
- Kidney protection in diabetes: Proven to slow the progression of diabetic nephropathy in patients with type 2 diabetes and hypertension
- Contraindicated in pregnancy: Must not be used during pregnancy as it can cause serious harm or death to the developing fetus
- Once-daily dosing: Taken once daily with or without food, starting at 150 mg for most adults with dose adjustments as needed
- Monitor potassium levels: Can increase serum potassium; avoid combining with potassium-sparing diuretics or potassium supplements without medical supervision
What Is Irbesartan Zentiva and What Is It Used For?
Irbesartan Zentiva contains the active substance irbesartan, which belongs to a group of medicines known as angiotensin II receptor antagonists (ARBs). It is used to treat high blood pressure (essential hypertension) in adults and to protect the kidneys in patients with type 2 diabetes and high blood pressure who have diabetic nephropathy.
High blood pressure, or hypertension, is a chronic condition affecting approximately 1.28 billion adults worldwide according to the World Health Organization. Often called a "silent killer," hypertension rarely causes noticeable symptoms but significantly increases the risk of heart attack, stroke, heart failure, and kidney disease. Controlling blood pressure is one of the most effective ways to reduce cardiovascular morbidity and mortality.
Irbesartan works by selectively blocking the angiotensin II type 1 (AT1) receptor. Angiotensin II is a powerful hormone produced by the renin-angiotensin-aldosterone system (RAAS) that causes blood vessels to constrict and stimulates the release of aldosterone, leading to sodium and water retention. By blocking the AT1 receptor, irbesartan prevents these effects, leading to vasodilation, reduced aldosterone secretion, and ultimately lower blood pressure.
Unlike ACE inhibitors (another class of RAAS-blocking drugs such as enalapril or ramipril), ARBs like irbesartan do not inhibit the breakdown of bradykinin. This is clinically significant because bradykinin accumulation is thought to be responsible for the dry, persistent cough that affects 5–20% of patients taking ACE inhibitors. As a result, irbesartan is often prescribed as an alternative for patients who cannot tolerate ACE inhibitors due to cough.
The kidney-protective effects of irbesartan have been demonstrated in landmark clinical trials, including the IRMA 2 (Irbesartan in Patients with Type 2 Diabetes and Microalbuminuria) and IDNT (Irbesartan Diabetic Nephropathy Trial) studies. These trials showed that irbesartan significantly reduced the progression of microalbuminuria to overt proteinuria and slowed the decline in renal function in patients with type 2 diabetes and hypertensive nephropathy, independent of its blood-pressure-lowering effect.
Irbesartan Zentiva is a generic version of irbesartan. It contains the same active substance in the same dose as the original branded product and works in the same way. Generic medicines undergo rigorous testing by regulatory authorities such as the European Medicines Agency (EMA) to ensure they are bioequivalent to the reference product.
What Should You Know Before Taking Irbesartan Zentiva?
Before starting Irbesartan Zentiva, tell your doctor about all medical conditions, current medications, and whether you are pregnant, planning to become pregnant, or breastfeeding. This medicine is contraindicated in pregnancy and must not be combined with certain other blood pressure medications in specific patient groups.
Contraindications
You must not take Irbesartan Zentiva if any of the following apply to you:
- Allergy to irbesartan or any excipient: If you have ever had a hypersensitivity reaction to irbesartan or any of the other ingredients in the tablet
- Pregnancy (second and third trimester): Use during pregnancy is contraindicated. If pregnancy is detected, irbesartan must be discontinued as soon as possible (see Pregnancy and Breastfeeding section below)
- Concomitant use with aliskiren in patients with diabetes mellitus or moderate-to-severe renal impairment (GFR < 60 ml/min/1.73 m2): Dual blockade of the RAAS increases the risk of hypotension, hyperkalemia, and renal impairment
- Severe hepatic impairment or biliary obstruction: Use in patients with severe liver disease has not been adequately studied
- Hereditary problems of galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption: The tablets contain lactose
Warnings and Precautions
Talk to your doctor before taking Irbesartan Zentiva if you have any of the following conditions, as extra monitoring or dose adjustments may be needed:
- Volume or sodium depletion: Patients who are volume-depleted (for example, from high-dose diuretic therapy, dietary salt restriction, dialysis, diarrhea, or vomiting) may experience symptomatic hypotension, especially after the first dose. Correct volume depletion before starting treatment, or begin with a lower dose of 75 mg.
- Renovascular hypertension: Patients with bilateral renal artery stenosis or stenosis to a solitary kidney are at increased risk of severe hypotension and renal insufficiency when treated with drugs that affect the RAAS.
- Renal impairment: Monitoring of potassium and creatinine levels is recommended. No dose adjustment is necessary in patients with mild to moderate renal impairment unless they are also volume-depleted.
- Heart failure: As with other RAAS-acting agents, there is a risk of severe hypotension and (more rarely) acute renal failure in patients with severe heart failure.
- Aortic and mitral valve stenosis or hypertrophic cardiomyopathy: Special caution is warranted as lowering blood pressure may be poorly tolerated.
- Primary hyperaldosteronism: Patients with primary hyperaldosteronism generally do not respond to antihypertensives acting through inhibition of the RAAS. Irbesartan is therefore not recommended.
- Hyperkalemia: Concomitant use with potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium may lead to dangerous increases in serum potassium. Regular monitoring is essential.
Pregnancy and Breastfeeding
Irbesartan Zentiva must not be used during pregnancy. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus. In the second and third trimesters, these drugs have been associated with fetal and neonatal toxicity including hypotension, renal failure, hyperkalemia, skull defects, and death. If you discover that you are pregnant while taking Irbesartan Zentiva, stop the medicine immediately and contact your doctor. Women of childbearing potential should use effective contraception throughout treatment.
Use during the first trimester is also not recommended. Although the evidence for teratogenicity from first-trimester exposure is less conclusive, the potential risk cannot be excluded. Switching to a safer alternative antihypertensive treatment should be carried out as soon as possible when planning pregnancy.
Breastfeeding: It is not known whether irbesartan is excreted in human breast milk. Due to the potential for adverse effects in the nursing infant, a decision must be made whether to discontinue breastfeeding or to discontinue the medicine, taking into account the importance of the therapy to the mother. As a precaution, it is preferable to avoid use during breastfeeding and to use alternative treatments with a better-established safety profile, especially while breastfeeding a newborn or pre-term infant.
How Does Irbesartan Zentiva Interact with Other Drugs?
Irbesartan can interact with several other medicines, potentially leading to dangerous drops in blood pressure, elevated potassium levels, or kidney damage. Always inform your doctor about all medications, supplements, and herbal products you take.
Drug interactions with irbesartan can be broadly categorized into major (clinically significant) and minor (requiring monitoring) interactions. The most clinically important interactions involve other drugs that affect the renin-angiotensin system or potassium balance. The table below summarizes the key interactions.
Major Interactions
| Interacting Drug | Effect | Recommendation |
|---|---|---|
| ACE inhibitors (e.g., enalapril, ramipril, lisinopril) | Dual RAAS blockade increases risk of hypotension, hyperkalemia, and acute renal failure | Avoid combination. Contraindicated in patients with diabetic nephropathy |
| Aliskiren | Dual RAAS blockade with increased adverse effects | Contraindicated in patients with diabetes or GFR <60. Avoid in others |
| Lithium | Increased lithium levels and toxicity (reversible) | Monitor lithium levels closely. Combination not recommended |
| Potassium-sparing diuretics (spironolactone, eplerenone, amiloride, triamterene) | Additive hyperkalemia risk; may be life-threatening | Avoid or use with close monitoring of serum potassium |
| Potassium supplements / salt substitutes | Elevated serum potassium | Avoid without medical supervision. Monitor potassium |
Minor Interactions
| Interacting Drug | Effect | Recommendation |
|---|---|---|
| NSAIDs (ibuprofen, naproxen, diclofenac) | May reduce antihypertensive effect; increased risk of renal impairment and hyperkalemia | Use with caution. Ensure adequate hydration. Monitor renal function |
| Thiazide diuretics (hydrochlorothiazide) | Additive blood pressure lowering; risk of first-dose hypotension | Often used intentionally in combination. Monitor blood pressure |
| Other antihypertensives | Enhanced blood-pressure-lowering effect | Monitor blood pressure during titration |
| Trimethoprim | Increased risk of hyperkalemia | Monitor potassium when used together |
Irbesartan is primarily metabolized by the liver enzyme CYP2C9 and, to a lesser extent, by glucuronidation. Inhibitors of CYP2C9 (such as fluconazole) may increase irbesartan plasma levels, although this is generally not considered clinically significant. No clinically relevant interactions have been observed with warfarin, digoxin, hydrochlorothiazide, or nifedipine in pharmacokinetic studies.
What Is the Correct Dosage of Irbesartan Zentiva?
The usual starting dose for adults with hypertension is 150 mg once daily, which may be increased to 300 mg once daily for additional blood pressure control. For diabetic nephropathy, the maintenance dose is 300 mg once daily. The tablet should be swallowed with water and can be taken with or without food.
Adults
Hypertension
Starting dose: 150 mg once daily. The blood pressure reduction begins within 1–2 hours after a single oral dose, with the maximum effect reached at 3–6 hours. The blood-pressure-lowering effect is sustained over 24 hours.
Maintenance dose: 150 mg once daily for most patients. If blood pressure is not adequately controlled after 4–6 weeks, the dose may be increased to 300 mg once daily. This is the maximum recommended dose.
Special starting dose (75 mg): A starting dose of 75 mg may be considered for patients who are volume-depleted (e.g., on high-dose diuretics) or undergoing hemodialysis.
Diabetic Nephropathy (Type 2 Diabetes with Hypertension)
Preferred maintenance dose: 300 mg once daily. Treatment should be initiated at 150 mg once daily and titrated up to 300 mg — the preferred dose for renal protection based on clinical trial evidence (IDNT and IRMA 2 studies).
Children and Adolescents
Irbesartan Zentiva is not recommended for use in children and adolescents under 18 years of age. The safety and efficacy have not been established in this age group. If antihypertensive treatment is required in children, other agents with pediatric evidence should be considered under specialist supervision.
Elderly Patients
No dose adjustment is generally required for elderly patients. However, treatment should be initiated with caution, particularly in patients over 75 years, as they may be more susceptible to hypotensive effects. Starting with the lower dose of 75 mg may be appropriate if there are concerns about volume status or renal function. Blood pressure, renal function, and electrolytes should be monitored regularly.
Patients with Renal or Hepatic Impairment
Renal impairment: No dose adjustment is needed for patients with mild to moderate renal impairment. For patients on hemodialysis, a starting dose of 75 mg is recommended. The medicine should be used with caution in severe renal impairment due to limited experience.
Hepatic impairment: No dose adjustment is generally necessary for patients with mild to moderate hepatic impairment. Irbesartan has not been studied in patients with severe hepatic impairment and should not be used in this population.
Missed Dose
If you forget to take your dose, take it as soon as you remember on the same day. If it is already close to the time for your next dose, simply skip the missed dose and take your next dose at the usual time. Do not take a double dose to make up for a missed one, as this may cause your blood pressure to drop too low.
Overdose
If you have taken more Irbesartan Zentiva than prescribed, or if someone else has accidentally taken your medicine, contact your local poison control center or seek emergency medical attention immediately. Symptoms of overdose are most likely to include low blood pressure (hypotension) and rapid heartbeat (tachycardia). Bradycardia (slow heartbeat) may also occur in some cases. There is no specific antidote. Treatment is supportive. Irbesartan is not efficiently removed by hemodialysis.
What Are the Side Effects of Irbesartan Zentiva?
Like all medicines, Irbesartan Zentiva can cause side effects, although not everybody gets them. Most side effects are mild and tend to resolve as the body adjusts. Common side effects include dizziness, nausea, and fatigue. Serious side effects such as hyperkalemia and severe hypotension are uncommon but require immediate medical attention.
The following side effects have been reported in clinical trials and post-marketing surveillance. They are organized by frequency according to international convention: very common (affects more than 1 in 10 people), common (1 in 10 to 1 in 100), uncommon (1 in 100 to 1 in 1,000), and rare (less than 1 in 1,000).
Very Common (>1/10)
Affects more than 1 in 10 people
- Hyperkalemia (elevated potassium) — in patients with diabetic nephropathy treated with irbesartan 300 mg
Common (1/10 – 1/100)
Affects 1 to 10 in every 100 people
- Dizziness, especially when standing up (orthostatic dizziness)
- Nausea and vomiting
- Fatigue and malaise
- Musculoskeletal pain (muscle and joint pain)
- Elevated creatine kinase levels
- Hypotension (low blood pressure), including orthostatic hypotension
Uncommon (1/100 – 1/1,000)
Affects 1 to 10 in every 1,000 people
- Tachycardia (rapid heartbeat)
- Flushing (redness and warmth of the skin)
- Cough (less common than with ACE inhibitors)
- Diarrhea
- Dyspepsia (indigestion) and heartburn
- Sexual dysfunction
- Chest pain
- Headache
Rare (<1/1,000)
Affects fewer than 1 in 1,000 people
- Angioedema (swelling of face, lips, tongue, or throat) — seek emergency help
- Hepatitis and abnormal liver function
- Jaundice (yellowing of the skin and eyes)
- Thrombocytopenia (low platelet count)
- Tinnitus (ringing in the ears)
- Severe allergic (hypersensitivity) reactions including rash, urticaria, and vasculitis
- Impaired renal function, including cases of renal failure in at-risk patients
- Hyponatremia (low sodium levels)
Contact your doctor or go to the nearest emergency department immediately if you experience any of the following: swelling of the face, lips, tongue, or throat (angioedema); difficulty breathing or swallowing; severe dizziness or fainting; yellowing of the skin or eyes; or an irregular heartbeat. These may be signs of a serious, potentially life-threatening reaction.
If you experience any side effects, including any not listed above, talk to your doctor or pharmacist. You can also report side effects directly to your national pharmacovigilance agency (for example, the Yellow Card Scheme in the UK, MedWatch in the USA, or the EMA in the EU). By reporting side effects, you can help provide more information on the safety of this medicine.
How Should You Store Irbesartan Zentiva?
Store Irbesartan Zentiva at room temperature below 30°C (86°F), protected from moisture and heat. Keep the tablets in their original packaging and out of the reach and sight of children.
Proper storage of medication is important to ensure that it remains effective and safe throughout its shelf life. Follow these guidelines for Irbesartan Zentiva:
- Temperature: Store below 30°C (86°F). Do not refrigerate or freeze.
- Moisture: Keep the tablets in the original blister pack or container to protect them from moisture.
- Light: Store in the original packaging to protect from light if indicated on the pack.
- Children: Keep out of the reach and sight of children. Store in a locked medicine cabinet if possible.
- Expiry date: Do not use after the expiry date (EXP) printed on the packaging. The expiry date refers to the last day of that month.
- Disposal: Do not throw away medicines via household waste or wastewater. Return unused or expired medicines to your pharmacy for safe disposal. This helps to protect the environment.
If you notice any visible changes to the tablets (discoloration, crumbling, unusual odor), do not take them and consult your pharmacist. Always check the expiry date before taking your medicine.
What Does Irbesartan Zentiva Contain?
Each film-coated tablet contains irbesartan as the active substance, along with several inactive ingredients (excipients) that are necessary for manufacturing the tablet and ensuring its stability.
Active substance: Each tablet contains 75 mg of irbesartan.
Other ingredients (excipients):
- Tablet core: Lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, hypromellose, silicon dioxide (colloidal anhydrous), magnesium stearate
- Film coating: Hypromellose, titanium dioxide (E171), macrogol 400, polysorbate 80
Appearance: Irbesartan Zentiva 75 mg tablets are white to off-white, biconvex, oval-shaped film-coated tablets. They are supplied in blister packs.
This medicine contains lactose monohydrate. If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicine. Patients with hereditary problems of galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption should not take this medicine.
Frequently Asked Questions About Irbesartan Zentiva
Irbesartan Zentiva is an angiotensin II receptor blocker (ARB) prescribed for two main indications: (1) treatment of essential hypertension (high blood pressure) in adults, and (2) treatment of kidney disease in adult patients with type 2 diabetes and high blood pressure (hypertensive diabetic nephropathy). It lowers blood pressure by blocking the action of angiotensin II, a hormone that causes blood vessels to constrict. In diabetic kidney disease, it has been proven to slow the progression of kidney damage, as demonstrated in the IDNT and IRMA 2 clinical trials.
No. Irbesartan Zentiva is strictly contraindicated during pregnancy, particularly during the second and third trimesters. It can cause serious harm to the developing fetus, including kidney failure, skull defects, and even death. If you become pregnant while taking this medicine, stop taking it immediately and contact your doctor, who will switch you to a safer alternative. Women of childbearing potential should use effective contraception during treatment. Use during the first trimester is also not recommended as a precautionary measure.
The most commonly reported side effects in clinical trials include dizziness (especially when standing up), nausea, vomiting, fatigue, and musculoskeletal pain such as muscle or joint aches. In patients treated for diabetic nephropathy at the 300 mg dose, hyperkalemia (elevated potassium levels) is very common. Most side effects are mild to moderate and tend to diminish as your body adjusts to the medication. If any side effect persists or worsens, contact your doctor.
While there is no absolute contraindication to drinking alcohol with irbesartan, alcohol can lower blood pressure on its own and may intensify the blood-pressure-lowering effect of the medicine. This can lead to increased dizziness, lightheadedness, or even fainting, especially when standing up from a seated or lying position. It is generally advisable to limit alcohol intake while on irbesartan and to discuss your drinking habits with your healthcare provider.
You can expect some blood pressure reduction within 1–2 hours of taking your first dose, with the peak effect occurring at 3–6 hours. However, the full therapeutic effect develops gradually over 4–6 weeks of consistent daily use. It is crucial to keep taking the medicine every day, even if you feel well, because high blood pressure usually has no noticeable symptoms. Stopping the medicine abruptly can lead to a rebound increase in blood pressure.
If you miss a dose, take it as soon as you remember on the same day. If it is almost time for your next scheduled dose, skip the missed one and continue with your regular dosing schedule. Never take a double dose to compensate for a missed dose, as this could cause your blood pressure to drop excessively. If you frequently forget doses, consider setting a daily alarm or using a pill organizer to help you remember.
References
- European Medicines Agency (EMA). Irbesartan — Summary of Product Characteristics (SmPC). EMA Product Database. Updated 2025. Available at: www.ema.europa.eu
- Lewis EJ, Hunsicker LG, Clarke WR, et al. Renoprotective effect of the angiotensin-receptor antagonist irbesartan in patients with nephropathy due to type 2 diabetes (IDNT). N Engl J Med. 2001;345(12):851–860. doi:10.1056/NEJMoa011303
- Parving HH, Lehnert H, Bröchner-Mortensen J, et al. The effect of irbesartan on the development of diabetic nephropathy in patients with type 2 diabetes (IRMA 2). N Engl J Med. 2001;345(12):870–878. doi:10.1056/NEJMoa011489
- Williams B, Mancia G, Spiering W, et al. 2018 ESC/ESH Guidelines for the management of arterial hypertension. Eur Heart J. 2018;39(33):3021–3104. doi:10.1093/eurheartj/ehy339
- World Health Organization (WHO). Hypertension Fact Sheet. WHO. Updated 2023. Available at: www.who.int
- National Institute for Health and Care Excellence (NICE). Hypertension in adults: diagnosis and management. NICE Guideline NG136. Updated 2025. Available at: www.nice.org.uk
- British National Formulary (BNF). Irbesartan monograph. NICE BNF. Updated 2025. Available at: bnf.nice.org.uk
- U.S. Food and Drug Administration (FDA). Avapro (irbesartan) — Prescribing Information. FDA. Available at: www.accessdata.fda.gov
- Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults. J Am Coll Cardiol. 2018;71(19):e127–e248. doi:10.1016/j.jacc.2017.11.006
- Kidney Disease: Improving Global Outcomes (KDIGO). KDIGO 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease. Kidney Int. 2021;99(3S):S1–S87.
About the Medical Editorial Team
This article was written and medically reviewed by the iMedic Medical Editorial Team, a multidisciplinary group of licensed physicians specializing in cardiology, clinical pharmacology, nephrology, and internal medicine. Our editorial process follows the GRADE evidence framework and adheres to the guidelines issued by international bodies including the WHO, EMA, FDA, ESC/ESH, NICE, and KDIGO.
Licensed physicians with expertise in clinical pharmacology and cardiovascular medicine. All medical claims are referenced to peer-reviewed literature and current prescribing information.
Independent review by board-certified specialists in cardiology, nephrology, and clinical pharmacology. Content is checked against the latest EMA SmPC, FDA prescribing information, and clinical guidelines.
Conflict of interest statement: The iMedic Medical Editorial Team has no financial relationships with pharmaceutical companies. All content is editorially independent with no commercial funding or sponsorship.