In early July 2018, it became known that a number of generic preparations containing the active substance valsartan could be carcinogenic. This news took caregivers and patients by surprise. Initially, a recall was initiated at the pharmacy level. A few weeks later, the recall was expanded to the patient level. The source of the contamination was a factory of the Chinese company Zhejiang Huahai Pharmaceutical, where the active ingredient valsartan is produced. It was found that batches from that factory had contained too high a concentration of N-nitrosodimethylamine since as early as 2012. The EMA estimates that if 5000 patients took the maximum dose of 320 mg of tainted valsartan tablets every day in the period from July 2012 to July 2018, there will be one extra case of cancer. The valsartan contamination raises the question of whether or not the Dutch authorities involved responded adequately. It has become clear from the contamination of valsartan that good and timely communication is important.