Irbesartan is an oral medication used primarily to treat high blood pressure (hypertension). It belongs to a class of drugs known as angiotensin receptor blockers (ARBs).

Irbesartan (Aprovel, Avapro) is an angiotensin receptor blocker that is available as oral 75 mg, 150 mg, and 300 mg tablets for the treatment of hypertension.

Irbesartan Uses:

• Diabetic nephropathy:
  • Treatment of diabetic nephropathy with elevated serum creatinine and proteinuria (>300 mg/day) in patients with type 2 diabetes and hypertension.
• Hypertension:
  • Management of hypertension
  • Guideline recommendations:
    • The 2017 Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults recommends that if monotherapy is warranted, in the absence of comorbidities (eg, cerebrovascular disease, chronic kidney disease, diabetes, heart failure, ischemic heart disease, etc.), that thiazide-like diuretics or dihydropyridine calcium channel blockers may be preferred options due to improved cardiovascular endpoints (eg, prevention of heart failure and stroke). ACE inhibitors and ARBs are also good for monotherapy.
    • Combination therapy may be required to achieve blood pressure goals and is initially preferred in patients at high risk (stage 2 hypertension or atherosclerotic cardiovascular disease [ASCVD] risk ≥10%).
• Off Label Use of Irbesartan in Adults:
  • Acute coronary syndrome (for secondary prevention of cardiovascular events)
  • Stable coronary artery disease

Irbesartan dose in adults:

Irbesartan dosage in the treatment of Hypertension:

Irbesartan for High Blood Pressure:

• Start with: 150 mg by mouth once a day.
• If needed, can increase to: 300 mg by mouth once a day.
• This is the highest daily dose.
• For patients who've lost a lot of body fluids: Start with 75 mg instead.

Irbesartan dosage in diabetic nephropathy:

For kidney problems due to diabetes (Diabetic nephropathy):

• Take 300 mg of Irbesartan by mouth once a day.

Irbesartan Dose in Children:

Irbesartan dose in the treatment of Hypertension:

For kids aged 6 and above with high blood pressure:

• Start with 75 mg by mouth once a day.
• If needed, can increase up to 150 mg once a day as the most you take.

For teenagers:

• Begin with 150 mg by mouth once a day.
• If needed, can increase up to 300 mg once a day as the most you take.

For children or teens who don't have enough fluids in their body:

• Start with half of the regular starting dose.

Irbesartan dose in reducing proteinuria in children with chronic kidney disease:

For children aged 4 and up, and teenagers:

• Doctors use a fixed dose based on weight groups (check below).
• They usually start with around 2 mg of irbesartan per kilogram of body weight, once a day.
• If needed, they can increase the dose after a few weeks based on blood pressure results.
• In the biggest study involving 44 children (average age: 10 years), they ended up with about 4 mg of irbesartan per kilogram of weight once a day.

Here are the starting doses based on weight:

• 10 to 20 kg: Start with 37.5 mg once a day.
• 21 to 40 kg: Begin with 75 mg once a day.
• Over 40 kg: Start with 150 mg once a day.

Pregnancy Risk Factor D

• Medications that affect the renin-angiotensin system can be harmful to an unborn baby and might lead to serious problems or even death.
• If a woman becomes pregnant while taking these medications, she should stop using them as soon as possible.
• These medications can cause a condition called oligohydramnios, which reduces the amount of amniotic fluid around the baby. This can cause problems like underdeveloped lungs and skeletal abnormalities in the baby.
• Sometimes, oligohydramnios doesn't show up until after damage to the baby has already occurred.
• Using these medications during pregnancy can also lead to problems like lack of urine, low blood pressure, kidney failure, underdeveloped skull, and baby's death.
• Babies exposed to these medications in the womb should be watched for issues like high potassium levels, low blood pressure, and low urine output. They might need special treatments like blood transfusions or dialysis.
• These risks are often connected with the use of these medications in the second and third trimesters of pregnancy.
• Just having high blood pressure during pregnancy, itself can cause problems for the baby like birth defects, low birth weight, early birth, stillbirth, and baby's death.
• Pregnant women with chronic high blood pressure are usually advised not to use medications from the angiotensin II receptor blocker class. These medications should generally be avoided by women who plan to become pregnant.

Irbesartan use during breastfeeding:

• We don't know if irbesartan gets into breast milk.
• Because of the risk of harm to the baby, you should decide either to stop breastfeeding or to stop taking the drug.
• Think about how important the treatment is for the mother.

Irbesartan Dose in Kidney Disease:

If you have mild to serious health issues:

• You don't need to change the dose unless you have a low body fluid level.

If you are on hemodialysis:

• The drug doesn't get removed from your body during the treatment.

Irbesartan Dose in Liver disease:

• No dosage adjustment is necessary.

Common Side Effects of Irbesartan (Aprovel):

• Endocrine & metabolic:
  • Hyperkalemia

Less Common Side Effects of Irbesartan (Aprovel):

• Cardiovascular:
  • Orthostatic dizziness
  • Orthostatic hypotension
• Central nervous system:
  • Dizziness
  • Fatigue
• Gastrointestinal:
  • Diarrhea
  • Dyspepsia
  • Heartburn

Contraindications to Irbesartan (Aprovel):

When not to use Irbesartan:

• If you're allergic to irbesartan or any part of the medicine.
• If you're taking a drug called aliskiren and have diabetes.

Note:

• We're not sure if people allergic to similar drugs will react to irbesartan. But since these drugs are similar, it's possible.

For Canadians:

• Don't use irbesartan with aliskiren if your kidneys aren't working well.
• Don't use it with ACE inhibitors if you have kidney problems due to diabetes.
• Don't take it if you have certain sugar problems like galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption.
• Avoid during pregnancy and breastfeeding.

Warnings and precautions

Angioedema

• Rarely, ARB medicines can cause angioedema. This is sudden swelling, especially under the skin.
• This swelling can happen at any time, even after the first dose.
• It might cause swelling in the head and neck area, which can make it hard to breathe. Or, it can cause belly pain if the intestines swell.
• People who've had angioedema without a known cause, inherited angioedema, or angioedema with ACE-inhibitors might be at a higher risk.
• If the tongue, voice box, or windpipe swells, it's serious. It can block the airway. People who've had throat surgeries might be at higher risk of this.
• If someone has angioedema symptoms, stop the ARB medicine right away.
• Quick treatment is very important. A shot of epinephrine might be needed.
• If someone had angioedema with an ARB before, don't give them ARBs again.

Hyperkalemia:

• Hyperkalemia means having too much potassium in the blood.
• Taking ARBs can sometimes cause this.
• People at higher risk are those with kidney problems, diabetes, or those taking certain medicines or supplements. These include water pills that keep potassium, potassium supplements, or salts that have potassium.
• If someone is at risk or using these other products, be very careful when using ARBs. Keep a close eye on potassium levels.

Hypotension

• Hypotension means low blood pressure.
• Starting irbesartan might cause low blood pressure in people who have low body fluids or salt, like those taking strong water pills (diuretics).
• If someone is low on fluids or salt, it's a good idea to fix that before giving irbesartan.
• If someone has a short period of low blood pressure when starting irbesartan, it doesn't mean they can't keep taking the medicine.

Renal function deterioration:

• Irbesartan might cause problems with kidney function. This can be seen as an increase in a blood test called serum creatinine.
• People most at risk are those with poor blood flow to their kidneys (like narrowed kidney arteries), existing kidney disease, serious heart failure, or low body fluids.
• In these people, their kidney function partly depends on a hormone system that irbesartan affects.
• In some cases, this could lead to very low urine output, kidney failure, and increasing waste products in the blood (azotemia).
• If there's a small rise in serum creatinine after starting the drug, think about stopping it only if the kidney function gets much worse or continually declines.

Aortic/mitral stenosis:

• If someone has notable narrowing of their aortic or mitral heart valves (known as stenosis), be careful when using irbesartan.

Ascites:

• Ascites means a buildup of fluid in the belly.
• Don't use irbesartan in people with ascites caused by liver scarring (cirrhosis) or ascites that doesn't respond to treatment.
• If you must use irbesartan in someone with cirrhosis-caused ascites, watch their blood pressure and kidney function closely. There's a risk of quick kidney failure.

Renal artery stenosis

• Renal artery stenosis means narrowing of the arteries that supply the kidneys.
• Be careful when using irbesartan in people with narrowing in one or both kidney arteries, especially if they don't have stents.
• If both kidney arteries are narrowed and don't have stents, it's usually best to avoid irbesartan. This is because of the high chance of kidney function getting worse. Only use it if the potential benefits are greater than the risks.

Renal impairment

• If someone already has kidney problems, be careful when using irbesartan.

Irbesartan: Drug Interactions

Monitoring parameters:

General Blood Pressure Guidelines (ACC/AHA [Whelton 2017]):

• People with confirmed high blood pressure and heart disease or high risk of heart disease (10-year risk ≥10%):
  • Recommended target: Below 130/80 mm Hg
• People with high blood pressure but without high risk of heart disease:
  • Target of below 130/80 mm Hg might be good.

For People with Diabetes and High Blood Pressure (ADA 2019):

• Age 18-65, no heart disease, and low risk of heart disease (10-year risk <15%):
  • Recommended target: Below 140/90 mm Hg
• Age 18-65 and with heart disease or high risk of heart disease (10-year risk >15%):
  • Target of below 130/80 mm Hg can be considered if safe.
• Over 65 years old (healthy or some health problems):
  • Recommended target: Below 140/90 mm Hg
• Over 65 years old (many health problems):
  • Recommended target: Below 150/90 mm Hg

How to administer Irbesartan?

• You can take it with food or on an empty stomach. It's flexible.

Mechanism of action of Irbesartan:

• Irbesartan is a type of drug that blocks the action of a substance called angiotensin II in the body.
• Angiotensin II makes blood vessels tighten (vasoconstriction) and triggers the release of a hormone called aldosterone.
• Aldosterone causes the body to reabsorb sodium and water, leading to higher blood pressure.
• Irbesartan attaches to a specific receptor (AT1) that angiotensin II would normally bind to.
• By doing this, irbesartan stops angiotensin II from causing blood vessels to constrict and from releasing aldosterone.
• This helps keep blood vessels relaxed and prevents excess sodium and water reabsorption, which can lower blood pressure.

In short, irbesartan works by blocking the effects of angiotensin II to help maintain healthy blood pressure levels.

Timing and Duration:

• It starts working in about 1 to 2 hours.
• The strongest effect is reached in 3 to 6 hours after taking it, and with long-term use, it takes around 2 weeks to reach maximum effect.
• The effect lasts more than 24 hours.

How it Moves in the Body:

• The body absorbs it quickly and completely.

Distribution:

• It spreads in a volume between 53 to 93 liters.

Binding and Metabolism:

• About 90% of it attaches to proteins in the blood, mainly albumin and alpha-1 acid glycoprotein.
• The liver processes it. This involves changing it through glucuronide conjugation and oxidation. A specific enzyme, CYP2C9, helps with the oxidation process.

How Much Gets into Circulation:

• When taken by mouth, 60% to 80% of the drug is absorbed and becomes available in the bloodstream.

Time it Takes to Leave the Body:

• The time it takes to clear half of the drug from the body is around 11 to 15 hours.

Peak in Blood Concentration:

• The highest amount of the drug in the blood is usually reached between 1.5 to 2 hours after taking it.

Getting Rid of the Drug:

• Around 80% of the drug is eliminated through the feces (stool).
• About 20% is excreted in the urine.

International Brands of Irbesartan:

• Avapro
• ACT Irbesartan
• AG-Irbesartan
• APO-Irbesartan
• Auro-Irbesartan
• Avapro
• BIO-Irbesartan
• DOM-Irbesartan
• JAMP-Irbesartan
• MINT-Irbesartan
• MYLAN-Irbesartan
• PMS Irbesartan
• Priva-Irbesartan
• RAN-Irbesartan
• RIVA-Irbesartan
• SANDOZ Irbesartan
• TEVAIrbesartan
• VAN-Irbesartan
• Agepin
• Andaran
• Angioblock MONO
• Aplorar
• Approvel
• Aprocare
• Aprovel
• Aprtan
• Arbit
• Arbitan
• Artibesan
• Atokken
• Avapro
• Besanta
• Besartin
• Bestar
• Bewel 300
• Bezart
• Converium
• Coravel
• Dynacard
• Elzar
• Fritens
• Gemot
• Gizlan
• Hypergold
• Ibefro
• Ibera
• Ibesaa
• Ibetan
• Ifirmasta
• Iprestan
• Irbador
• Irbartan
• Irbec
• Irbedrin
• Irbee
• Irbegen
• Irbemed
• Irbenox
• Irbesan
• Irbesel
• Irbesof
• Irbetan
• Irbeten
• Irbett
• Irbevell
• Irbevex
• Irbezyd
• Irbis
• Ircovas
• Irebeprex
• Iretensa
• Irovel
• Irprestan
• Irstran
• Irtan
• Irvebal
• Irvell
• Isart
• Izatan
• Karvea
• Nortens
• Optima
• Presolin
• Rycardon
• Tensiber
• Virbez
• Zatrivir
• Zatrivit
• Ziorel

Irbesartan Brand Names in Pakistan: