Teva Pharmaceuticals Co. Ltd., of Jerusalem, initiated a voluntary recall in the U.S. to the patient level, of 35 lots of bulk losartan potassium USP Tablets (six lots of 25-mg strength and 29 lots of 100-mg strength), due to the detection of N-nitroso-n-methyl-4-aminobutyric acid found in six lots of active pharmaceutical ingredient manufactured by Hetero Labs Ltd., of Hyderabad, India, that is above the FDA's interim acceptable exposure limit.