Losartan vs Avapro

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For patients with hypertension or heart disease, certain drugs that help control blood pressure by blocking the action of a hormone called angiotensin II can significantly reduce their risk of stroke and other complications. Losartan and Avapro are two such medications often prescribed for this purpose. They both work as angiotensin II receptor blockers (ARBs) but have varying effects on the cardiovascular system. Losartan not only blocks angiotensin receptors but also has an active metabolite that provides a longer duration of action compared to Avapro. On the other hand, Avapro (Irbesartan) is known for its high binding affinity to the angiotensin receptors and slower dissociation from these receptors, offering consistent blood pressure control throughout the day.

What is Losartan?

Losartan (sold under the brand name Cozaar among others) is an angiotensin II receptor antagonist drug used primarily to treat high blood pressure. It was the first of this class of drugs to be approved by the FDA in 1995. Losartan works by blocking the binding of angiotensin II to its receptors, which causes vessels to relax and reduces blood volume, effectively lowering blood pressure. It is prescribed for patients with hypertension and can also slow down damage to kidneys caused by type 2 diabetes.

On similar lines, Irbesartan (the generic name for Avapro) belongs to the same class as Losartan but received FDA approval a few years later in 1997. Much like Losartan, it lowers blood levels by preventing Angiotensin II from constricting blood vessels. However, compared with Losartan, Avapro has a longer duration of action that allows once-daily dosing and comes with slightly different side effect profiles due to their selectivity towards angiotensin receptors.

What conditions is Losartan approved to treat?

Losartan is approved for the treatment of several conditions, including:

  • Hypertension, more commonly known as high blood pressure
  • Stroke prevention in patients with hypertension and left ventricular hypertrophy (LVH)
  • Diabetic nephropathy, which is kidney disease that results from diabetes. This is specifically for type 2 diabetic patients who have a certain level of protein in their urine

How does Losartan help with these illnesses?

Losartan works to manage hypertension by blocking the action of angiotensin II, a hormone that can constrict blood vessels and promote the release of another hormone called aldosterone. Aldosterone can cause an increase in sodium and water reabsorption, which contributes to higher blood volume and pressure. Losartan is classified as an angiotensin receptor blocker (ARB) because it prevents angiotensin II from binding with receptors on blood vessels, thus allowing them to dilate or expand. This mechanism reduces overall blood pressure, helping those with hypertension maintain healthier levels. Because it also limits the effects of aldosterone, losartan helps reduce fluid buildup—an aspect beneficial for patients dealing with heart failure or kidney disease along with their high blood pressure.

What is Avapro?

Avapro, also known as irbesartan, is an angiotensin II receptor antagonist that works by blocking the action of certain natural substances that tighten the blood vessels and lead to reduced salt and water retention. This allows the blood to flow more smoothly and the heart to pump more efficiently. It was first approved by the FDA in 1997. Unlike some other medications used for hypertension like Losartan, Avapro does not break down into an active metabolite meaning it has a simpler metabolic pathway which may be beneficial for certain patients with complex medication regimes or those with liver conditions where drug metabolism can be impaired. Its side-effect profile is generally well tolerated but may include dizziness or upset stomach while serious side effects such as changes in urination or signs of kidney problems are rare but should prompt immediate medical attention. The benefits on smooth muscle relaxation make it a suitable choice for treatment of high blood pressure especially in patients who do not respond sufficiently to other classes of antihypertensive drugs.

What conditions is Avapro approved to treat?

Avapro has been approved for the treatment of:

  • Hypertension (high blood pressure)
  • Diabetic nephropathy (a condition characterized by damage to the small blood vessels in the kidneys, often seen in patients with diabetes)

This medication helps relax and widen your blood vessels, allowing better blood flow and reducing overall blood pressure.

How does Avapro help with these illnesses?

Angiotensin II is a hormone that can constrict blood vessels, cause the release of another hormone called aldosterone, and increase the retention of sodium and water. These actions can raise blood pressure. Avapro works by blocking the effects of angiotensin II at its receptor, thereby helping to lower blood pressure. Its ability to inhibit this hormonal system may also be beneficial in treating conditions like diabetic nephropathy or kidney disease due to diabetes. While losartan operates similarly as an angiotensin receptor blocker (ARB), Avapro might be prescribed when patients experience certain side effects with losartan or require different dosing options available with Avapro.

How effective are both Losartan and Avapro?

Both losartan (Cozaar) and irbesartan (Avapro) are potent antihypertensive agents, belonging to the class of angiotensin II receptor blockers (ARBs). They were approved by the FDA within a few years of each other in the mid-1990s. Since they act on similar receptors, they are prescribed under comparable circumstances such as hypertension or diabetic nephropathy. The effectiveness of losartan and irbesartan was directly compared in several studies; both drugs exhibited similar efficacy in managing high blood pressure and had similar safety profiles.

A 2004 meta-analysis reports that both medications effectively lower systolic and diastolic blood pressure with minimal side effects. Notably, Losartan has a shorter half-life requiring twice-daily dosing while Irbesartan is usually taken once daily due to its longer duration of action.

In terms of usage prevalence, according to a 2016 review, losartan appears more frequently prescribed worldwide than irbesartan. This could be attributed partially to its earlier introduction into medical practice providing it with an extensive history and study for its effectiveness in treating hypertension.

Nonetheless, choice between losartan or irbesartan typically depends on individual patient factors such as tolerance to medication regimen or specific comorbid conditions rather than differences in their performance at controlling blood pressure alone. Both these ARBs have been proven effective against placebo for treating hypertension but direct comparison trials suggest no significant difference between them.

abstract image of a researcher studying a bottle of drug.

At what dose is Losartan typically prescribed?

Oral dosages of Losartan typically range from 25–100 mg/day for treating high blood pressure in most adults, and studies have indicated that a daily dose of 50 mg is usually sufficient. For children aged 6 to 16 years, the dosage may start at 0.7 mg/kg up to 50 mg once per day. In either population, dosage can be increased after a few weeks if there's no adequate response or as prescribed by the doctor. The maximum dosage that should not be exceeded in any case is generally considered to be 100 mg/day.

At what dose is Avapro typically prescribed?

Avapro therapy typically begins with a daily dose of 150 mg. If necessary, this can be increased to 300 mg/day, administered once daily. It's important to allow for an adjustment period; if blood pressure levels are not adequately controlled after several weeks on the initial dosage, only then should your physician consider increasing the dosage or adding other hypertension medications. The maximum recommended dose is 300 mg per day. As always, follow your healthcare provider's instructions carefully when taking Avapro or any medication.

What are the most common side effects for Losartan?

Common side effects of Losartan may include:

  • Dizziness or lightheadedness due to a drop in blood pressure
  • Nasal congestion, cold-like symptoms
  • Persistent cough
  • Fatigue and asthenia (general weakness)
  • Diarrhea
  • Orthostatic hypotension (a form of low blood pressure that happens when you stand up from sitting or lying down)
  • Spinning sensation (vertigo)
  • Increased potassium levels in the blood

On the other hand, Avapro might cause similar but some different side effects such as:

  • Dizziness and fatigue
  • Nausea or upset stomach
  • Heartburn -Diarrhea -Skin rash or itching -Muscle pain

Always remember these are potential side effects; not everyone taking these medications will experience them. Always consult with your healthcare provider for any concerns regarding medication usage.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Losartan?

Losartan and Avapro are two commonly prescribed drugs for managing high blood pressure. However, they can occasionally lead to severe side effects such as:

  • Signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
  • An increase in potassium levels leading to symptoms like slow heart rate, weak pulse, muscle weakness or limp feeling.
  • Kidney issues: little or no urination.
  • Symptoms indicating a breakdown of skeletal muscle tissue - unexplained muscle pain or tenderness, muscle weakness especially if you also have fever and dark colored urine.
  • Severe skin reactions - fever, sore throat burning in your eyes; skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) causing blistering and peeling.

It is crucial that if you experience any of these symptoms while taking Losartan or Avapro that you seek immediate medical attention.

What are the most common side effects for Avapro?

Avapro, also known as irbesartan, may have side effects such as:

  • Nausea or upset stomach
  • Diarrhea
  • Heartburn
  • Dizziness or lightheadedness
  • Tiredness
  • Ringing in the ears
  • Muscle pain or cramps
  • Changes in urine frequency and volume These side effects can occur when beginning Avapro but should lessen over time. If they persist or worsen, it is essential to contact your healthcare provider promptly.

Are there any potential serious side effects for Avapro?

While Avapro is typically well-tolerated, it can cause some serious side effects in rare cases. These may include:

  • Signs of an allergic reaction such as hives, difficulty breathing or swallowing, swelling of the face, lips, tongue or throat
  • A light-headed feeling like you might pass out
  • Little to no urination
  • High potassium level leading to nausea, weakness, tingly feeling, chest pain and irregular heartbeats
  • Kidney problems characterized by painful or difficult urination; swelling in your hands and feet; fatigue or shortness of breath

If any of these symptoms occur while taking Avapro, contact your healthcare provider immediately.

Contraindications for Losartan and Avapro?

Both Losartan and Avapro, like many other angiotensin receptor blockers (ARBs), may cause certain side effects in some individuals. If you notice worsening symptoms such as lightheadedness, rapid or irregular heartbeat, severe nausea or vomiting, please seek immediate medical attention.

Neither Losartan nor Avapro should be taken if you are taking, or have been taking medication that increases potassium levels like potassium supplements or salt substitutes containing potassium. Always inform your physician which medications you're currently taking; these drugs will require careful monitoring to prevent dangerous interactions with Losartan and Avapro.

Additionally, it's crucial to avoid using Losartan or Avapro if you're pregnant since ARBs can potentially harm the fetus. Always consult your healthcare provider for advice about when it is safe to use these medicines during pregnancy.

How much do Losartan and Avapro cost?

In terms of brand-name medications, a 30-tablet supply of Avapro (150 mg) can cost up to $180, which equates to around $6 per day. Cozaar, a brand name for Losartan that comes in 50 mg tablets, is less expensive; it averages about $130 for a 30-day supply or roughly $4.33 per day.

However, if you are prescribed higher dosages (i.e., Avapro: 300mg/day or Losartan: 100mg/day), the price difference between these two drugs may not be as significant. It's important to note that cost should not be your primary consideration when choosing medication. The effectiveness and suitability of the drug for your specific health condition matter most.

The generic versions of these drugs offer much more affordability:

  • Generic losartan can range from around $10-$15 for a month’s supply depending on dosage strength.
  • On the other hand, irbesartan (generic Avapro) costs approximately $15-$25 per month.

These prices make both options typically under one dollar per day regardless of dose administered.

Popularity of Losartan and Avapro

Losartan, also available under the brand name Cozaar, is a widely prescribed antihypertensive drug that belongs to the class of angiotensin II receptor blockers (ARBs). In 2020, it was estimated that about 37 million people in the US were prescribed Losartan. This drug accounted for just over 18% of ARB prescriptions in the US and has been steadily growing in prevalence since its FDA approval in 1995.

Irbesartan, sold under the brand Avapro among others, is another member of the ARBs class and was prescribed to approximately 2.3 million people in the USA during 2020. In terms of ARB prescriptions within America, irbesartan accounts for just under 4%. Although effective and well-tolerated like Losartan, its use has remained relatively steady over recent years without significant increases or decreases observed.


Both Losartan and Avapro (Irbesartan) have been widely used in patients with hypertension, and their effectiveness is well-documented in numerous clinical studies. They both belong to a class of medications known as angiotensin II receptor blockers (ARBs), which work by blocking the action of certain natural substances that tighten the blood vessels, allowing the blood to flow more smoothly.

Losartan has a broader application than Avapro, being also prescribed for reducing stroke risk in certain patients with enlarged hearts, while Avapro is often recommended for kidney disease treatment associated with diabetes.

Both drugs are available in generic form representing significant cost savings especially for those paying out of pocket. The effects may not be immediate upon starting either medication; there might be an adjustment period where your body gets used to the medication before you begin noticing changes.

As far as side effects go, both Losartan and Avapro are generally well-tolerated but can cause similar side effects such as dizziness or lightheadedness due to lowered blood pressure. More serious side effects like kidney problems or increased potassium levels should prompt immediate medical attention. As always, it's crucial that patients closely monitor their reactions when starting these treatments.