What is valsartan, and how does it work (mechanism of action)?

WARNING [update 10/15/2019]: Today, the U.S. Food and Drug Administration posted a warning letter to Torrent Pharmaceuticals in Ahmedabad, Gujarat, India. Torrent manufactures losartan potassium tablets and has been one subject of an ongoing global investigation into nitrosamine impurities in angiotensin II receptor blockers (ARBs) such as valsartan, losartan and irbesartan.

The warning letter outlines several manufacturing violations at Torrent’s Taluka-Kadi, Indrad, Gujarat facility, including failure to follow written procedures for production and process control and failure to adequately investigate batch discrepancies. Failure to correct these violations may result in further action by the agency. The warning letter is another result of the agency’s ongoing investigation.

FDA reminds patients taking recalled ARBs to continue taking their current medicine until their pharmacist provides a replacement or their doctor prescribes a different medication that treats the same condition.

What is valsartan, and how does it work (mechanism of action)?

Valsartan is an oral medication that is used to treat high blood pressure and congestive heart failure. It belongs to a class of drugs called angiotensin receptor blockers (ARBs) which also includes irbesartan (Avapro), losartan (Cozaar), and candesartan (Atacand). Angiotensin, formed in the blood by the action of angiotensin converting enzyme (ACE), is a powerful chemical that attaches to angiotensin receptors found in many tissues but primarily on smooth muscle cells of blood vessels. Angiotensin’s attachment to the receptors causes the blood vessels to narrow (vasoconstrict) which leads to an increase in blood pressure (hypertension). Valsartan blocks the angiotensin receptor. By blocking the action of angiotensin, valsartan dilates blood vessels and reduces blood pressure. Valsartan was approved by the FDA in December 1996.