(CBS News) — Americans who take prescription drugs to control blood pressure should check their medical cabinets once again. Macleods Pharmaceuticals is recalling another 32 lots of widely used losartan potassium tablets sold nationwide after finding trace amounts of a probable carcinogen.

The recall involves losartan and potassium/hydrochlorothiazide combination pills found to contain N-Nitroso-N-methyl-4-aminobutyric acid, or NMBA, according to a notice posted by the U.S. Food and Drug Administration.

“Based on the available information, the risk of developing cancer in a few patients following long-term use of the product cannot be ruled out,” the notice stated.

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