Olmesartan, commercialised for hypertension, is no more effective than the other sartans or than ACEs (angiotensin-converting enzyme inhibitors) against the cardiovascular complications of hypertension.

Since mid-2012, excessive, sometimes severe, gastrointestinal adverse effects (enteropathies) with diarrhoea, sometimes intense abdominal pains, weight loss, etc. have been observed particularly with olmesartan, compared with other sartans or ACEs. A French study carried out in 2014 revealed 10 times more hospitalisations for enteropathy with olmesartan than with other sartans or ACEs.

In February 2015, the pharmacovigilance committee of the French health products agency (ANSM) voted unanimously to withdraw olmesartan-based drugs from the market. In April 2015, the Transparency Committee proposed stopping their reimbursement because of this risk, "after a period of one year" – a very generous period for the pharmaceutical companies.

As of early 2016, olmesartan was still being widely prescribed, with no reduction in the number of prescriptions despite the warning given by Prescrire in 2013 and that by the ANSM in mid-2014, and with cases of enteropathy still being reported.

In April 2016, French authorities announced that olmesartan would no longer be reimbursed by France's national health insurance system, effective July 2016. 

It is in patients' best interests to avoid olmesartan, to review current treatments and replace it with another antihypertensive drug from the same or another family, devoid of this risk.

It is a matter of urgency for the health authorities to withdraw marketing authorisations for all olmesartan-based drugs to avoid exposing patients needlessly.

©Prescrire 1 May 2016

"Olmesartan: sprue-like enteropathy" Prescrire Int 2016; 25 (171): 130-131. (Pdf, subscribers only).