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Benicar Side Effects


Benicar and Benicar HCT are prescription treatments for high blood pressure. They can lead to serious intestinal side effects, including diarrhea and Celiac-like symptoms.

Nearly 67 million Americans deal with high blood pressure, and many of them keep hypertension in check with medicines like Benicar (olmesartan medoxomil). Benicar and similar drugs like Benicar HCT, Azor (amlodipine/olmesartan) and Tribenzor (olmesartan/amlodipine/hydrochlorothiazide) can also reduce the risk of serious cardiovascular problems. But while these prescription medications have their benefits, they also can produce side effects that lead to serious health problems. Severe gastrointestinal problems rank as the most significant threats. Specifically, the conditions are sprue-like enteropathy – a disease with Celiac-like symptoms – and villous atrophy – which damages the ability of the small intestine to absorb nutrients. Symptoms include severe, chronic diarrhea, malnutrition and substantial weight loss. Doctors may misdiagnose these diseases as Celiac because of the symptomatic similarities among the disorders. In the case of Celiac, blood tests will show the presence of antibodies. For atrophy and sprue-like enteropathy, patients who take the offending drugs may not notice symptoms for several years after use. The U.S. Food and Drug Administration (FDA) ordered that warnings about these side effects be added to the drug labels under Warnings and Precautions, but former patients responded more personally. Many of them filed lawsuits against the maker of Benicar and other similar medications, Daiichi Sankyo, Inc, stating the company failed to warn them about the potentially life-alter side effect from their products.

Severe Intestinal Damage and FDA Warning

The FDA issued a drug safety alert for Benicar in July 2013 after it reviewed data submitted by the Mayo Clinic in 2012. The FDA found a number of former Benicar users who reported severe diarrhea and weight loss after taking the medication. Some of them also developed severe intestinal damage. Initially, doctors at Mayo Clinic thought a number of patients who took Benicar had Celiac disease, but blood tests came back negative. They noticed a common thread between patients with this painful intestinal disease was Benicar. No other drug in the same class caused the Celiac-like symptoms of a disease called sprue-like enteropathy. Symptoms improved once patients stopped taking the drug. "The FDA's evaluation found clear evidence of an association between olmesartan and sprue-like enteropathy. If patients taking olmesartan develop these symptoms and no other cause is found, the drug should be discontinued and therapy with another antihypertensive started,” the agency stated in its warning. Authors of the FDA report called these side effects "life-threatening." For example, one patient in the Mayo study lost 125 pounds. Many others took steroids to try and control intestinal inflammation. Out of the 22 patients in the study, 14 ended up in the hospital. "There is no question that the report from the Mayo Clinic documenting that olmesartan has severe gastrointestinal adverse effects is of concern," Dr. Franz Messerlim told MedPage Today. Messerlim is director of the hypertension program at St. Luke's-Roosevelt Hospital in New York City.

Additional Studies

Doctors at the Mayo Clinic were not the only ones who linked Benicar and related drugs to resulting intestinal issues. The American College of Gastroenterology connected an additional 40 cases of sprue-like enteropathy to olmesartan-based blood pressure medicines in October 2012. Benicar has other side effects, too. It damages the walls of the intestines. This condition called villous atrophy causes the villi that line intestinal walls to erode, preventing them from absorbing nutrients and causing patients to become malnourished. Researchers noted the condition after taking samples of tissue from patients that took olmesartan and complained of chronic diarrhea. In a May 2013 study published in the American Journal of Gastroenterology, researchers reported that patients who were negative for Celiac disease actually had olmesartan-related villous atrophy. Discontinuing use of the drug allowed patients to gain weight back and lessened symptoms.

Other Side Effects and Black Box Warning

Benicar also has a number of other side effects, including a black box warning for fetal toxicity. According to the label, pregnant women should not take Benicar and the medicine should be stopped immediately once a woman knows she is pregnant. The drug can "cause injury of death to the developing fetus." Additional side effects from clinical trials and post market reports include:
  • Angioedema (rapid swelling of the skin)
  • Vomiting
  • Irregular heart beat
  • Abdominal pain
  • Nausea
  • Chest pain
  • Arthritis
  • Rash
  • Kidney problems, including failure
  • Liver impairment
  • Hair loss

Benicar Lawsuits

A number of attorneys filed lawsuits on behalf of their clients against the maker of Benicar, Daiichi Sankyo, Inc., its parent company, Daiichi Sankyo Co. Ltd., and Forest Laboratories Inc., a company alleged to be involved in promoting Benicar. Forest acknowledged in public company filings that it received subpoena requests from the U.S. Attorney for the District of Massachusetts in 2011 for documents related to Benicar, Benicar HCT and Azor. The company admitted to being involved in “approximately six actions” about Benicar allegations related to gastrointestinal “injuries.” Daiich Sankyo is defending Forest in the claims. (Forest earned contract revenue of $93.2 million in the final three quarters of 2013 and $101.6 million for the final three quarters of 2012.) To pay for the defense of any lawsuits filed before April 1, 2014, Forest has insurance coverage of $140 million of product liability insurance coverage. Approximately 1.9 million patients filled prescriptions for Benicar and other olmesartan-based ARB medicines in the U.S. in 2012, according to a report published by GI and Hepatology News, an American Gastroenterological Association (AGA) Institute publication. The U.S. Department of Justice claimed Daiichi Sankyo paid illegal kickbacks to doctors who prescribed Benicar, violating the False Claims Act. The company settled the case for $39 million in April of 2015. The whistleblower in the case received $6.1 million, and the rest of the settlement went to various states. If you take Benicar or a similar medication to manage your blood pressure, it is vital that you do not ignore gastrointestinal symptoms and related symptoms like unexplained or unusual weight loss. These gastrointestinal side effects can be very serious, impacting health for years, perhaps even resulting in permanent damage and huge financial burdens for affected patients. Some patients are turning to the legal system for help.