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Benicar Overview


The prescription medication Benicar was designed to treat high blood pressure. But in some people, the drug can have serious gastrointestinal side effects including intestinal damage, chronic diarrhea, malnourishment and severe weight loss. This led some patients and their families to file lawsuits against Daiichi Sankyo and Forest Laboratories.

What is Benicar?

Japanese drugmaker Daiichi Sankyo, Inc. developed the popular prescription medication Benicar (olmesartan medoxomil ) to treat high blood pressure. It was originally approved by the U.S. Food and Drug Administration (FDA) in 2002, and today doctors write more than 11 million prescriptions a year for the drug.

The medication’s active ingredient, olmesartan medoxomil, lowers the body’s blood pressure by helping to keep blood vessels dilated (open). The drug can be taken as a stand-alone blood-pressure treatment or as part of a combination of drugs. Other drugs that contain olmesartan include Benicar HCT, Azor (amlodipine/olmesartan) and Tribenzor (olmesartan/amlodipine/hydrochlorothiazide).

Gastrointestinal Side Effects

Benicar is a popular choice for many doctors to prescribe to patients. However, research surfaced linking Benicar and other olmesartan-based drugs to severe gastrointestinal side effects. In April 2014, this research led the FDA to rule that Benicar needed a warning on its label stating olmesartan medoxomil was associated with specific and significant gastrointestinal side effects.

These side effects can mimic Celiac disease but usually are later diagnosed as sprue-like enteropathy or villous atrophy. Both are serious problems that can lead to malnutrition, intestinal damage and chronic diarrhea. Some people who took the medication filed lawsuits against Daiichi Sankyo after suffering from these drug-induced illnesses.

How Does Benicar Work?

Benicar, Azor and Tribezor all contain olmesartan, a medication that belongs to a group of drugs called angiotensin II receptor blockers (ARB). Angiotensin II is a natural protein made by the body that affects the cardiovascular system in a variety of ways, including controlling blood pressure.

When angiotensin II is released, it causes blood vessels to narrow, raising blood pressure and making it harder for the heart to pump blood. This protein also increases the amount of sodium and fluid in the body and increases blood pressure. Olmesartan blocks angiotensin II and stops it from constricting blood vessels to help blood flow more easily.

Serious Side Effects

Gastrointestinal Problems

Of the side effects caused by Benicar, the most severe are gastrointestinal problems that resemble Celiac disease – an allergy to the wheat protein found in grains. Symptoms include: chronic diarrhea, dramatic weight loss and stomach pain and discomfort.

Testing for Celiac

Once symptoms present themselves, doctors typically test for Celiac. If Celiac gets discounted, these conditions are called sprue-like enteropathy and villous atrophy. Researchers found that with patients taking Benicar or related drugs, symptoms improved only after patients stopped taking the medication(s).

Possible Hospitalization

Unfortunately, some patients suffer with these symptoms for years, losing unhealthy amounts of weight and going from doctor to doctor for their condition. Some have had to be hospitalized.

Other Side Effects of Benicar:
Abdominal pain Angioedema (rapid swelling of the skin)
Chest pain Hair loss
Liver impairment Nausea
Rash Vomiting
Arthritis Irregular heart beat
Kidney problems, including failure

Mayo Clinic Research

The Mayo Clinic contacted the FDA in 2012 because their researchers found a connection between specific gastrointestinal symptoms and olmesartan medoxomil. Between 2008 and 2011, Mayo Clinic saw 22 patients with symptoms similar to those associated with Celiac disease, including chronic diarrhea, malabsorption of nutrients, and significant weight loss. Tests for Celiac disease returned negative, but all of these patients took Benicar.

Researchers concluded that olmesartan could cause serious gastrointestinal side effects and should be used with care. They also found that no other drug in the same class caused these problems. Following the Mayo Clinic’s notice, the FDA in July 2013 added a warning to Benicar’s prescribing information.

Black Box Warning

The drug’s label also includes a black box warning – the FDA’s strongest warning – for fetal toxicity. This means that taking the drug while pregnant can harm the fetus. Pregnant women should not take olmesartan, and it should be discontinued immediately (under doctor supervision) as soon as a woman knows she is pregnant.

Benicar Lawsuits

People who took Benicar, Azor or Tribenzor can suffer physically and financially. Some patients underwent long and difficult treatments trying to ease the severe intestinal complications and other health issues triggered or caused by these medications.

A growing number of people are picking the legal system as a way to receive compensation for medical bills, pain, suffering and other damages – and to send a message to drug maker Daiichi Sankyo. Soon after the FDA’s 2013 warning, former Benicar users filed the first lawsuits in New Jersey against Daiichi Sankyo, Inc. Judges moved those cases to federal court.

One man, George Williams, spent more than 100 days in the hospital after taking Benicar. His digestive system is so damaged he must now use a feeding tube. His complaint accuses the defendant of concealing the dangers of the drug and failing to warn the public.