Figure 2.

The structures of the US-marketed ARB molecules, with tetrazole ring circled when present. Panel A shows molecules containing a tetrazole ring and for which selected lot of some products have been removed from the market via publicly announced recalls (valsartan, irbesartan, losartan) or through an unspecified mechanism (olmesartan). Panel B shows the structure of candesartan, an ARB molecule containing a tetrazole ring; no recalls related to nitrosamine impurities have affected candesartan products as of now. Panel C shows US-marketed ARB molecules that do not contain a tetrazole ring, none of which has been affected by recalls.