Valsartan (a generic version of Diovan) might have become contaminated with the chemical N-nitrosodimethylamine (NDMA) if produced by Zhejiang Huahai Pharmaceuticals or Hetero Labs Limited. Potential injuries include liver damage, tumors, and cancer.

In May 2018, the European Medicines Agency (EMA) began reviewing certain medicines containing valsartan.  In July 2018, the FDA announced that three companies were voluntarily recalling their medications containing valsartan that was supplied by the Chinese company Zhejiang Huahai Pharmaceuticals. The recall occurred after the company determined the presence of NDMA in the valsartan.  Several drug companies have voluntarily recalled their blood pressure and heart medication that contains valsartan after it was discovered that the medication might have become contaminated in the Chinese and India manufacturing plants it was being produced.