(ProPublica) – ProPublica decided to test several generic versions of three of the most widely prescribed drugs in the United States: the antidepressant bupropion XL, the generic for Wellbutrin XL; the heart medicine metoprolol succinate, the generic for Toprol XL; and the cholesterol drug atorvastatin, the generic for Lipitor. A total of 11 samples from readers, ProPublica employees and the independent testing lab Valisure were assessed, representing a cross section of manufacturers from around the world.

Some were analyzed for impurities such as lead or whether their dosage levels matched the claims on their labels. Another test scrutinized the speed at which the tablets dissolved — a critical indicator of how medication is released in the body — and compared the results to the brand-name drugs. 

While most of the samples passed, the findings showed that one version of bupropion and one version of metoprolol, dispensed at least tens of thousands of times in 2024 alone, had irregularities that experts say could compromise their effectiveness. (Read More)