High blood pressure, or hypertension. is a health concern of millions of Americans. Because it can lead to other health problems, it’s important to treat hypertension as quickly as possible. For this reason, millions take blood pressure medication like Benicar to control the condition. However, many who took Benicar later developed a gastrointestinal problem known as sprue-like enteropathy, which has symptoms similar to those of celiac disease.

Daiichi Sankyo, the manufacturer of Benicar, has faced thousands of lawsuits from plaintiffs claiming that the company had not only used overly aggressive marketing tactics but had also failed to adequately warn of the risks of sprue-like enteropathy. In 2017, Daiichi Sankyo settled for around $300 million to close out more than 2,500 cases.

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What Is Benicar?

Benicar (olmesartan) is an angiotensin receptor blocker (ARB) antihypertensive medication used to treat high blood pressure. It may cause a serious gastrointestinal side effect known as sprue-like enteropathy, which is similar to celiac disease. 

When Was Benicar Approved by the FDA?

Benicar (olmesartan medoxomil) was approved by the Food and Drug Administration in 2002 to treat high blood pressure (hypertension). It is a member of the “angiotensin receptor blockers” (ARB) class of anti-hypertensive medications.

Who Manufactures Benicar?

Benicar is manufactured and marketed in the US by the Daiichi Sankyo, the second-largest pharmaceutical company in Japan. Daiichi Sankyo sells pharmaceutical, medical, and agricultural products in 50 countries and reports about $12 billion in annual revenue. Between 2010 and 2013, Benicar was selling at a yearly rate of about 11 million U.S. prescriptions and brought $3 billion per year in global revenue.

What Is the Active Ingredient in Benicar?

The active ingredient in Benicar (olmesartan) is also one ingredient in combination high-blood pressure medications such as Benicar HCT (olmesartan with hydrochlorothiazide, a diuretic), Azor (olmesartan with amlodipine, a calcium channel blocker), and Tribenzor (olmesartan with hydrochlorothiazide and amlodipine).

How Is Benicar Different from Other Blood Pressure Medications?

Unlike other members of the ARB class of blood pressure medications, Benicar has been shown to increase the risk of a serious gastrointestinal side effect known as “sprue-like enteropathy” which may cause severe, chronic diarrhea and significant weight loss and is similar to symptoms of celiac disease. Multiple lawsuits have been filed against Daiichi Sankyo for serious injury related to Benicar use and more may be expected to follow.

What Does Benicar Treat?

Benicar is a medication that is used to treat hypertension, also known as high blood pressure.

What Is Hypertension?

Hypertension, or high blood pressure, is a common health condition that millions of people across the United States suffer from. Around half of American adults experience hypertension and of those, around one-fifth are treated with recommendations for lifestyle changes. Many others are given prescription medications.

High blood pressure means that the pressure of the blood as it pushes against the walls of the arteries is consistently too high. High blood pressure can be dangerous because it forces the heart to work harder to pump blood throughout the body.

What Is Blood Pressure?

Blood pressure is the amount of pressure your blood puts on the walls of the arteries and may be affected by two things:

  • How much blood the heart pumps out
  • How quickly the blood can move through the arteries

Narrow arteries, whether because of genetics or because of cholesterol buildup, may cause the blood to move more slowly. If the heart is pumping out more blood and the arteries are narrower, high blood pressure may occur. There are two different types of hypertension.

What Is Primary Hypertension?

Primary hypertension is also called essential hypertension. This type of hypertension may occur gradually and has no known cause.

What Is Secondary Hypertension?

Secondary hypertension is high blood pressure that is caused by a specific underlying condition such as:

  • Congenital heart defects
  • Tumors on the adrenal glands
  • Thyroid issues
  • Obstructive sleep apnea
  • Kidney disease
  • Drug use
  • Certain medications, such as those for:
    • Cold and cough
    • Birth control
    • Pain relief
    • Other prescriptions

How Is Blood Pressure Measured?

Blood pressure is measured in mm Hg, which is milligrams of mercury. Normal blood pressure measures at around 120/80 mm Hg or lower. Your blood pressure is considered elevated if the top number (systolic pressure) is over 130 or the bottom number (diastolic pressure) is over 90, or both.

What Are the Stages of Hypertension?

There are two stages of hypertension:

  • Stage 1: 130-139/80-89 mm Hg
  • Stage 2: 140 or higher/90 or higher mm Hg

If your blood pressure is 180/120 mm Hg or higher, it’s considered an emergency and you should seek medical attention immediately.

What Are the Risks of Hypertension?

Hypertension puts extra strain on the heart and can increase the risk of stroke, heart attack, heart disease, and other health problems. This is why it’s important for you to regularly get your blood pressure checked and why it’s considered a normal part of any doctor’s visit for anyone over the age of 18.

What Are the Symptoms of Hypertension?

Symptoms may vary depending on the person. Some may experience the following symptoms:

  • Nosebleeds
  • Headaches
  • Shortness of breath

Hypertension may be a “silent disease”, with few symptoms. Symptoms may only occur when high blood pressure becomes life-threateningly severe and some may never experience them, even if their blood pressure is dangerously high.

What Are the Risk Factors for Hypertension?

Some people are more at risk of developing hypertension than others. It’s possible to have a high blood pressure measurement simply because you’re in the doctor’s office and may be anxious. This is called “white coat hypertension” and can occur when you’re getting a health checkup.

Hypertension is usually diagnosed only after multiple measurements show high blood pressure.

Other factors that can affect your risk for hypertension include:

  • Age
  • Obesity
  • Race
  • Genetics
  • Use of tobacco
  • Vaping
  • Drinking too much alcohol
  • Consuming too much salt
  • Low levels of potassium
  • Not enough exercise
  • Stress
  • Kidney disease
  • Sleep apnea
  • Diabetes
  • Pregnancy

Who Can Get Hypertension?

Usually, adults are more at risk of hypertension than children unless there’s an underlying health condition causing high blood pressure. However, there are increasing numbers of children experiencing high blood pressure due to lifestyle habits like a lack of exercise and a poor diet.

What Complications Can Hypertension Cause?

It’s important to treat hypertension because it maybe dangerous.

The following are complications that may result from high blood pressure:

  • Heart attack
  • Heart failure
  • Stroke
  • Aneurysm
  • Eye problems
  • Kidney issues
  • Dementia
  • Changes to memory, understanding, and thinking
  • Metabolic syndrome

How Does Benicar Work?

Benicar is an inhibitor of the angiotensin-II receptor, also known as an angiotensin receptor blocker (ARB) or a “sartan” because of the generic name olmesartan. The ARB class of anti-hypertensives works by blocking the activity of angiotensin-II in the cardiovascular system.

What Is Angiotensin-II?

Angiotensin-II is a product of the liver which is intended to regulate the blood pressure system. When the protein is produced by the liver, it has a vasoconstrictive effect that tightens the blood vessels and raises blood pressure. Increased blood pressure makes the heart work harder to pump blood through the body and can damage other organs such as the kidneys. 

Blocking angiotensin-II may help to lower blood pressure by stopping vasoconstriction. This may help the blood flow more freely through the vessels and decrease the work the heart must do to supply the body with blood and oxygen.

What Are the Side Effects of Benicar?

Benicar and medications containing olmesartan may have a number of side effects. Like most medications, many of these side effects are mild to moderate but may have a negative impact on the patient’s quality of life. In other cases, however, side effects are more severe and may be life-threatening.

What Are the Common Side Effects of Benicar?

Some common side effects of taking Benicar may include:

  • Rash
  • Hair loss
  • Arthritis
  • Nausea and vomiting
  • Irregular heartbeat
  • Chest pain
  • Angioedema (swelling of the skin)
  • Liver and kidney impairment

If side effects worsen or become bothersome, they may indicate a more serious medical problem and should be reported to a physician.

How Can Benicar Affect the GI System?

Benicar may also cause a much more severe adverse event affecting the gastrointestinal system in a condition known as “sprue-like enteropathy.” In July 2013, the FDA began requiring a warning about the gastrointestinal side effects of Benicar including sprue-like enteropathy.

Sprue-like enteropathy may cause severe symptoms that are similar to celiac disease, but testing may show the patient does not have celiac disease. Dietary changes normally recommended for celiac patients will not usually help those with Benicar-related gastrointestinal illnesses.

What Is Sprue-Like Enteropathy?

In 2012, the Mayo Clinic released a report regarding the occurrence of “sprue-like enteropathy” in multiple patients. These patients had symptoms that were similar to celiac disease but tested negative for the disorder. In addition, dietary changes normally recommended for celiac patients, such as eliminating all gluten from the diet, did not resolve the illness. All of the identified patients had been taking Benicar.

After discontinuation of the medication, some of the patients saw improvement in their symptoms but others may have suffered permanent damage. In July 2013, the FDA required that a warning be added to the prescribing information on Benicar regarding the risk of gastrointestinal effects. Benicar, and other products containing olmesartan, is the only member of the ARB class that has been shown to cause this side effect.

What Are the Symptoms of Sprue-Like Enteropathy?

The symptoms of sprue-like enteropathy may include:

  • Severe and chronic diarrhea
  • Weight loss
  • Abdominal pain
  • Bloating
  • Nausea
  • Vomiting
  • Anemia
  • Fatigue
  • Nutrient malabsorption

Doctors will often test for celiac disease when a patient reports these symptoms. Unfortunately, in some cases even if Benicar is discontinued, the patient will continue to suffer from the gastrointestinal illness, and they will not respond to traditional celiac regimens.

Some patients have suffered from sprue-like enteropathy for multiple years, seen multiple physicians, and may have been hospitalized for the illness. In addition, some patients may have permanent injury to the gastrointestinal system with a condition known as “villous atrophy” which results in a permanent lack of ability of the GI system to absorb nutrients.

Some cases of villous atrophy may be so severe that the small intestine allows larger undigested food particles to pass into the bloodstream. These particles can cause a severe immune reaction, resulting in body-wide inflammation and a number of food sensitivities.

Has the FDA Warned About Benicar?

The top of the prescribing information for Benicar includes a black-box warning. A black-box warning is the most severe warning that a medication can have and is placed inside a box with a thick black border so that it is readily seen by healthcare professionals who prescribe the medication.

Benicar’s black-box warning indicates a high risk of the development of birth defects and the possibility of fetal death in pregnant women who take Benicar. Benicar or other products containing olmesartan should not be taken by women who are pregnant or intend to become pregnant.

Why Is Daiichi Sankyo Facing Legal Trouble?

The maker of Benicar has faced legal trouble multiple times over Benicar. The company received warnings from the FDA in 2006 and 2013 due to its claims about Benicar and the risks associated with the use of the drug. There have also been concerns about Benicar research trials which were run for only three months, when most people require blood pressure medications for much longer. It is believed that had the studies been conducted under real use conditions, side effects of the drug mayhave been more evident prior to the drug’s release.

In addition, some independent reviews of adverse event data showed that Daiichi Sankyo should have been aware of the increased GI complaint rate but Daiichi failed to include this information in marketing material.

Why Are People Filing Benicar Lawsuits?

A number of patients who were injured after taking Benicar sued the manufacturer, Daiichi Sankyo Inc. Some patients may have been required to undergo years of medical treatments. They have claimed extreme pain and physical debility related to drug injuries including gastrointestinal complaints and other health conditions such as nutrient malabsorption and weight loss.

Some patients may have required hospitalization to treat drug injury complications and may have been left with permanent injury or disability such as the failure of the digestive system or the need for a permanent feeding tube.

Daiichi Sankyo is reported to have spent approximately $1 billion in aggressive promotions claiming Benicar was superior to other ARBs with an increased safety and efficacy profile which was not proven. Daiichi Sankyo was twice warned by the FDA for making false or misleading claims about the medication including unsubstantiated claimss, and risks which were not included in marketing materials.

What Benicar Lawsuit Settlements Are There?

Multiple lawsuits were filed against Daiichi Sankyo for aggressive promotion, deceptive advertising, and failure to warn the medical community and patients about the increased risk of side effects and permanent injury. In 2017, Daiichi Sankyo and co-marketer Forest Laboratories announced they would be spending up to $300 million to settle lawsuit claims against Benicar, Benicar HCT, Azor, and Tribenzor for sprue-like enteropathy and other severe GI complaints.  This settlement agreement was reported to cover at least 2,300 cases already filed and a number that may have been expected.

Notwithstanding claims relating to this product, the drug/medical device remains approved by the U.S. FDA. 


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